JP6529235B2 - Tire molding presser and tire molding method - Google Patents

Description

  The present invention relates to a tire molding pressing device for pressing a clinch portion of sidewall rubber in a molding process of a pneumatic tire, and a tire molding method using the tire molding pressing device.

  Generally, in the process of manufacturing a pneumatic tire, a green tire is formed by winding and pressing various tire rubber members around a cylindrical tire former.

  FIG. 4 is a view schematically showing a conventional tire molding pressing device. As shown in FIG. 4, after the tire rubber material 102 such as an inner liner or carcass ply is wound around a cylindrical tire former (not shown), the clinch portion 103a and the cushion portion 103b are integrally formed. A green tire is formed by further winding and pressing side wall rubber 103 cut to a fixed size.

  At this time, the starting end of the sidewall rubber 103 cut to a fixed length is attached to the tire molding former on which the tire rubber material 102 is wound, and the clinch roller 205 (free roller) of the tire molding holding device 200 is used. The tire molding former is rotated while pressing the clinch portion 103 a of the sidewall rubber 103. As a result, the clinch roller 205 is rotated along with the tire molding former, and the clinch portion 103a is sequentially crimped to the tire rubber material 102. Finally, the winding start and end portions of the clinch portion 103a are joined.

  On the other hand, the cushion portion 103b is sequentially crimped to the tire rubber material 102 by pressing the cushion portion 103b with a pressure roller (not shown) that rotates in accordance with the rotating tire molding former, and finally the cushion portion 103b The winding start and end portions of the are jointed. In addition, the code | symbol 201 in FIG. 4 is a holding | pressing cylinder which raises / lowers the clinch roller 205, 202 is a bearing, 204 is a roller axis | shaft.

JP, 2011-102023, A

  However, in the case of the above-described conventional tire molding method, a crack may occur in the joint portion of the clinch portion 103a after the joint. This is because the sidewall rubber 103 is composed of a clinch portion 103a and a cushion portion 103b different in composition, and the clinch portion 103a uses a rubber material having a larger amount of shrink than the cushion portion 103b. .

  That is, since the clinch portion 103a of the sidewall rubber 103 after cutting tends to shrink larger (3 to 5 mm) than the cushion portion 103b, the joint amount of the clinch portion 103a is insufficient in the joint amount and a crack is easily generated. Become.

  Therefore, conventionally, the sidewall rubber 103 is cut and wound so as to be about 5 mm longer than the fixed length in consideration of the amount of shrinkage of the clinch portion 103a. In this case, the cushion having a small amount of shrinkage is used. The joint amount is too large at the portion 103b, and there is a possibility that a bulge (bulge) may occur after manufacturing the tire.

  As described above, in the conventional molding method, when the cushion portion 103b is made appropriate with respect to the joint amount of the sidewall rubber 103, the clinch portion 103a is broken and a defective product is generated, and the clinch portion 103a is made appropriate. There is a problem that appearance quality may be deteriorated due to the occurrence of a bulge, and in any case, it is necessary to rework, and there is a possibility that manufacturing efficiency may be reduced.

  Therefore, the present invention can appropriately prevent the generation of defective products due to cracking of the clinch portion and the deterioration of the appearance quality due to the generation of bulges in the cushion portion during winding of sidewall rubber in the tire forming process. The task is to provide.

  The present inventors diligently studied the solution to the above-mentioned problems, and found that the above-mentioned problems could be solved by the invention described below, and completed the present invention.

The invention according to claim 1 is
A tire molding pressing device comprising a clinch roller for pressing the clinch portion of sidewall rubber in which a cushion portion and a clinch portion are integrally molded among tire constituent members wound around a rotating cylindrical tire molding former And
A pressure roller for a cushion, which rotates with the rotation of the tire molding former;
Braking means for applying rotational resistance to the clinch roller;
And control means for controlling the braking means.
The braking means stretches the clinch portion by pressing the clinch portion while applying rotational resistance to the clinch roller, and is configured to adjust a joint amount in the clinch portion.
Furthermore, the braking means is an air brake attached to the roller shaft of the clinch roller,
The control means
Adjust the application of the rotational resistance necessary to extend the clinch portion by the same length as the shrink amount measured in advance corresponding to the compounding amount of the rubber constituting the clinch portion, and further adjust the clinch roller by controlling the air pressure supplied to the air brake, characterized in that the rotational resistance applied to the clinch rollers are adjusted to electropneumatic proportional valve such that the shrinkage of the clinch portion is offset It is a pressing device for tire molding.

The invention according to claim 2 is
It is characterized in that it is used in a single molding machine which continuously performs both primary molding for bonding the inner liner and the carcass ply and secondary molding for bonding the sidewall rubber and the tread rubber on the above-described tire molding former. It is a holding | maintenance apparatus of the tire shaping | molding of Claim 1 .

The invention according to claim 3 is
A tire molding method in which the clinch portion of sidewall rubber in which a cushion portion and a clinch portion are integrally molded is crimped to a tire rubber material using the tire molding holding device according to claim 1 or 2. There,
The tire forming method is characterized in that the clinch portion is stretched by pressing the clinch portion while applying rotational resistance to the clinch roller by the braking means, and the joint amount in the clinch portion is adjusted.

The invention according to claim 4 is
The tire molding method according to claim 3 , characterized in that a sidewall rubber having a width of 85 to 220 mm and a thickness of 15 mm or less is used as the sidewall rubber.

The invention according to claim 5 is
The tire according to claim 3 or 4 , wherein the rotational resistance to the clinch roller is adjusted by the control means such that the amount of extension of the clinch portion after pressing is 7.5 mm or less. It is a method.

  According to the present invention, there is provided a technology capable of appropriately preventing the generation of defective products due to cracking of the clinch portion and the deterioration of the appearance quality due to the generation of bulges in the cushion portion during winding of sidewall rubber in the tire forming process. Can be provided.

It is a figure showing typically a pressing device for tire formation concerning a 1 embodiment of the present invention. FIG. 1 is a schematic view of a tire molding presser according to an embodiment of the present invention. It is a graph which shows the relationship between the brake pressure given to a clinch roller, and the amount of extension of a clinch part. It is a figure which shows typically the conventional tire pressing device.

  Hereinafter, the present invention will be described based on the embodiments with reference to the drawings.

1. Outline of Tire Forming Presser Device According to the Present Embodiment FIG. 1 is a view schematically showing a tire forming press device according to the present embodiment.

  As shown in FIG. 1, the tire molding pressing device 1 according to the present embodiment is a tire constituting member wound around a rotating tire molding former (not shown) as in the conventional tire molding pressing device. A clinch roller 34 is provided which presses the clinch portion 6a of the sidewall rubber 6 in which the cushion portion 6b and the clinch portion 6a are integrally formed, and rotates with the rotation of the tire-forming former.

  However, the tire molding pressing device 1 according to the present embodiment includes an air brake 35 as a braking means for applying rotational resistance to the clinch roller 34, and a control means (not shown) for controlling the air brake 35. In the prior art, the air brake 35 is configured to stretch the clinch portion 6a by pressing the clinch portion 6a while applying rotational resistance to the clinch roller 34 to adjust the joint amount in the clinch portion 6a. It is different from the tire molding presser.

  As a result, as described below, when the sidewall rubber is wound around the tire forming former in the tire forming process, the joint amount of each of the clinch portion and the cushion portion can be set to an appropriate value, so that the side Both the cracking of the wall rubber clinch portion and the occurrence of a bulge at the cushion portion can be appropriately prevented.

2. Specific Configuration of Tire Forming Press Retaining Device According to Present Embodiment The press forming device 1 according to the present embodiment will be described in detail. In the following description, a rubber member in which an inner liner, a carcass ply, and the like are laminated to set a bead 5a is referred to as "a tire rubber material 5".

  In the tire molding pressing device 1 according to the present embodiment, the roller shaft 33 is rotatably inserted in the rod portion 31 a of the device main body 30 via the bearing 32. A clinch roller 34 is attached to one end of the roller shaft 33, and an air brake 35 as a braking means for applying a rotational resistance to the clinch roller 34 is attached to the other end.

  It is preferable to use an air brake that can obtain a static friction torque of 9 N · m or more as this air brake 35. As such an air brake, Asahi exhibits a static friction torque of 13.7 N · m at an air pressure of 0.6 MPa. Seiko Instruments Inc. BSM, 7X can be mentioned.

  Further, a pressing cylinder 31b is provided in the apparatus main body 30, and adjusting the pressing force when the clinch roller 34 presses the clinch portion 6a by moving the clinch roller 34 up and down via the rod portion 31a. Can.

  FIG. 2 is a schematic view of a tire molding presser according to the present embodiment. As shown in FIG. 2, in the present embodiment, an electro-pneumatic proportional valve 36 is provided as control means for controlling the air brake 35, and the air brake 35 and the electro-pneumatic proportional valve 36 are provided via the air supply pipe 37. Is connected. For example, ITV 2050 (voltage type DC 0 to 10 V) manufactured by SMC Corporation is used as the electropneumatic proportional valve 36.

  The electropneumatic proportional valve 36 is electrically connected to a PLC (Programmable Logic Controller) 41, and the PLC 41 is further connected to an IPC (Industrial PC) 42.

  The IPC 42 prestores specification information (air pressure corresponding to the rubber composition of the clinch portion) of a plurality of product tires, selects the specification information according to the product tires being manufactured, and transmits the selected information to the PLC 41. The PLC 41 transmits, to the electro-pneumatic proportional valve 36, a pressure adjustment signal (current of DC 0 to 10 V) which is an analog signal based on the specification information transmitted from the IPC 42.

  The electro-pneumatic proportional valve 36 adjusts the air pressure supplied to the air brake 35 to an unauthorized floor based on the received pressure adjustment signal and controls the air brake 35 to cope with the rubber compounding of the clinching part to be pressed. The rotational resistance can be applied to the clinch roller 34.

  When the tire-forming former is rotated while pressing the clinch portion 6a with the clinch roller 34 to which such rotational resistance is applied, the rotation of the tire-forming former and the rotation of the clinch roller 34 are deviated, and the tire-forming is formed. A force along the circumferential direction of the tire-forming former is applied to the clinch portion 6a wound around the former to stretch the clinch portion 6a.

  Then, since the winding start end of the clinch portion 6a and the end portion in the stretched state are joined, the joint amount of the clinch portion 6a is obtained without cutting the sidewall rubber 6 longer than the fixed length. Can be adjusted to an appropriate value (1 to 5 mm) according to the amount of shrinkage of the clinch portion 6a. As a result, it is possible to appropriately prevent the occurrence of a crack in the clinch portion 6a after the joint.

  At this time, since the cushion portion 6b of the sidewall rubber 6 is joined by a pressing roller (not shown) for the cushion, which rotates with rotation of the tire molding former, as in the conventional case, the joint of the cushion portion 6b is made in advance. By cutting the side wall rubber 6 with a fixed length so that the amount becomes an appropriate value, the cushion portion 6b can be joined in a state where the appropriate value is maintained. As a result, the occurrence of a bulge in the cushion portion 6b can be prevented.

  As a result, according to the present embodiment, the joint amount of both the clinch portion 6a and the cushion portion 6b which are integrally formed is made an appropriate value, and both the crack of the clinch portion 6a and the bulge in the cushion portion 6 are obtained. The occurrence can be prevented, and the frequency of repair for correcting the cracks in the clinch portion 6 a and the bulge in the cushion portion 6 can be reduced to improve the manufacturing efficiency.

  The amount of shrinkage of the clinch portion 6a changes in accordance with the composition of the rubber constituting the clinch portion 6a, but in the present embodiment, as described above, the specification information of a plurality of product tires is stored in advance in the IPC 42. Since the rotation resistance applied to the clinch roller 34 is adjusted based on the specification information, the joint amount of the clinch portion 6a can be appropriately adjusted according to the type of the product tire. .

  Further, in the present embodiment, the pressing force with which the clinch roller 34 presses the clinch portion 6 a can be adjusted by moving the clinch roller 34 up and down using the holding cylinder 31 b. The pressing force at this time is preferably adjusted to 0.58 MPa. As a result, the clinch portion 6a can be sufficiently pressed to be crimped to the tire rubber material 5.

  In addition, as sidewall rubber 6 wound around a tire-forming former, sidewall rubber having a width of 85 to 220 mm and a thickness of 15 mm or less is preferably used.

  Further, the speed at which the clinch roller 34 rolls on the clinch portion 6 a to press the clinch portion 6 a is preferably 15 m / min.

  Also, although depending on the type of product tire, it is preferable to adjust the rotational resistance to the clinch roller by the braking means so that the amount of extension of the clinch portion 6a is 7.5 mm or less, and such an amount of extension is obtained It is preferable to control the air pressure supplied to the air brake 35 so that

  Hereinafter, the present invention will be specifically described based on examples.

1. Investigation of Brake Pressure In this example, first, in the tire molding presser according to the above-described embodiment, an appropriate value of the rotational resistance (brake pressure) applied to the clinch roller was examined.

(1) Investigation of the amount of shrinkage First, three types of sidewall rubbers having different blends (blends A to C) of the clinch portion are prepared, and the start and end portions of each sidewall rubber are butted (joint After leaving for a predetermined time at an amount of 0 mm), the gap formed in the clinched part after shrinking was measured, and the shrinking amount of the clinched part was examined. The survey results are shown in Table 1. In Table 1, the shrink amount of the clinch portion is represented as a negative joint amount.

(2) Investigation of the brake pressure and the amount of extension of the clinch portion Using the tire molding and holding device 1 according to the above-described embodiment, the pressing force by the holding cylinder 31b is set to 0.58 MPa, and the three types of blending described above The clinch portion 6 a was pressed by the clinch roller 34. At this time, the rotation resistance (brake pressure) applied to the clinch roller 34 by the air brake 35 is adjusted in the range of 0.1 to 0.5 MPa, and the elongation of the clinch portion 6a of the compound A to compound C at each brake pressure The amount (mm) was measured. The relationship between the brake pressure applied to the clinch roller and the amount of extension of the clinch portion is shown in Table 2 and FIG.

  From Tables 1 and 2 and FIG. 3, in the case of using a compound A rubber having a shrink amount of 4 mm, the brake to the clinch roller 34 is used to extend the clinch portion 6 a by 4 mm so that the shrink amount is offset. It can be seen that it is preferable to set the pressure to 0.27 MPa.

  In addition, in the case of the combination B in which the amount of shrinkage is 5 mm, in order to extend the clinch portion 6 a by 5 mm so that the amount of shrinkage is offset, it is preferable to set the brake pressure to the clinch roller 34 to 0.5 Mpa. I understand. Similarly, it is understood that in the case of the combination C in which the amount of shrinkage is 5.5 mm, in order to extend the clinch portion 6a by 5.5 mm, it is preferable to set the brake pressure to 0.35 Mpa. Preferred brake pressures for each formulation are shown in Table 3.

2. Molding of Green Tire (1) Manufacturing Conditions A green tire was molded by applying a preferable brake pressure to each combination obtained by the above-described test, and the occurrence of cracks in the clinch portion and bulges in the cushion portion was examined.

  Specifically, the green tire was formed by pressing the sidewall rubber having the clinched portions of the formulations A to C using the press device for forming a tire according to the above-described embodiment. At this time, as shown in Table 3, a preferable brake pressure for each composition was applied to the clinch roller. In addition, 150 green tires were formed for each composition, and the cut length of the sidewall was set so that the joint amount of the clinch portion after pressing was 2 mm. Moreover, the pressing force by the holding cylinder was set to 0.58 MPa.

(2) Results As a result of visual observation of the formed green tire, no crack was generated in the clinch portion after the joint in any of the sidewall rubbers of Formulation A to Formulation C. Moreover, as a result of confirming the product tire which vulcanized the formed green tire, generation | occurrence | production of the bulge in a cushion part was not seen. From this result, by pressing the clinch portion while applying an appropriate brake pressure (rotational resistance) to the clinch roller 34, the joint amount of the clinch portion is adjusted to an appropriate value, and the crack in the clinch portion and the bulge of the cushion portion It has been confirmed that it can prevent

  As mentioned above, although the present invention was explained based on an embodiment, the present invention is not limited to the above-mentioned embodiment. Various modifications can be made to the above embodiment within the same and equivalent scope of the present invention.

DESCRIPTION OF SYMBOLS 1, 200 Tire molding presser 5, 102 Tire rubber material 5a Bead 6, 103 Side wall rubber 6a, 103a Clinch part 6b, 103b Cushion part 30 Apparatus main body 31a Rod part 31b, 201 Press cylinder 32, 202 Bearing 33, 204 roller shaft 34, 205 clinch roller 35 air brake 36 electropneumatic proportional valve 37 air supply pipe 41 PLC
42 IPC

Claims (5)

A tire molding pressing device comprising a clinch roller for pressing the clinch portion of sidewall rubber in which a cushion portion and a clinch portion are integrally molded among tire constituent members wound around a rotating cylindrical tire molding former And
A pressure roller for a cushion, which rotates with the rotation of the tire molding former;
Braking means for applying rotational resistance to the clinch roller;
And control means for controlling the braking means.
The braking means stretches the clinch portion by pressing the clinch portion while applying rotational resistance to the clinch roller, and is configured to adjust a joint amount in the clinch portion.
Furthermore, the braking means is an air brake attached to the roller shaft of the clinch roller,
The control means
Adjust the application of the rotational resistance necessary to extend the clinch portion by the same length as the shrink amount measured in advance corresponding to the compounding amount of the rubber constituting the clinch portion, and further adjust the clinch roller by controlling the air pressure supplied to the air brake, characterized in that the rotational resistance applied to the clinch rollers are adjusted to electropneumatic proportional valve such that the shrinkage of the clinch portion is offset Tire molding presser. It is characterized in that it is used in a single molding machine which continuously performs both primary molding for bonding the inner liner and the carcass ply and secondary molding for bonding the sidewall rubber and the tread rubber on the above-described tire molding former. A tire molding presser according to claim 1 . A tire molding method in which the clinch portion of sidewall rubber in which a cushion portion and a clinch portion are integrally molded is crimped to a tire rubber material using the tire molding holding device according to claim 1 or 2. There,
A tire molding method, characterized in that the clinch portion is stretched by pressing the clinch portion while applying rotational resistance to the clinch roller by the braking means, and the joint amount in the clinch portion is adjusted. The tire molding method according to claim 3 , wherein a sidewall rubber having a width of 85 to 220 mm and a thickness of 15 mm or less is used as the sidewall rubber. The tire according to claim 3 or 4 , wherein the rotational resistance to the clinch roller is adjusted by the control means such that the amount of extension of the clinch portion after pressing is 7.5 mm or less. Method.

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