Ply joint inspection method and ply joint inspection device

Abstract

A ply joint inspection method according to the present disclosure includes: a rubber member winding step for winding a belt-like rubber member on a drum outer circumferential surface of a molding drum; a separator disposing step for disposing a separator on a portion of the belt-like rubber member in the drum circumferential direction on an outer side in the drum radial direction; a ply winding step for winding a ply so as to cover the belt-like rubber member and the separator from the outer side in the drum radial direction; a jointing step for, while holding both end portions of the ply in the drum circumferential direction on the separator, abutting and jointing end surfaces of the both end portions to each other; and an inspection step for irradiating a joint part jointed by the jointing step with light from an inner side in the drum radial direction by a lighting part provided on the separator, and detecting a defect in the joint part by using passage light that passes through the joint part.

Description

Ply joint inspection method and ply joint inspection device

[0001] The present disclosure relates to a ply bond inspection method and a ply bond inspection apparatus.

[0002] Conventionally, a tire building method has been known that includes a step of winding plies around the outer peripheral surface of a building drum and joining the end faces of the plies together. Patent Document 1 discloses this type of tire building method.

[0003] Special table 2017-523926 publication

[0004] After the end faces of the plies are butted together and joined, it is possible to inspect the joint of the plies to ensure the quality of the joined joint. One possible inspection method is to inspect the cylindrically molded ply from the inside using an inspection device while irradiating light from the outside using a light irradiation device.

[0005] However, when a cylindrical ply is molded so that it overlaps the radial outside of another cylindrical component such as an inner liner or side rubber, even if light is irradiated onto the ply joint, the light is blocked by the other cylindrical component, making it difficult to inspect the ply joint.

[0006] The present disclosure aims to provide a ply joint inspection method and ply joint inspection device that can inspect ply joints even when a cylindrical ply is molded so as to be overlapped radially outside another cylindrical member.

[0007] A ply joint inspection method according to a first aspect of the present disclosure includes: (1) a rubber member winding step of winding a band-shaped rubber member on the outer peripheral surface of a building drum; a separator placement step of placing a separator on a portion of the drum circumferentially outer side of the band-shaped rubber member in the drum radial direction; a ply winding step of winding a ply to cover the outer sides of the band-shaped rubber member and the separator in the drum radial direction; a joining step of butting end faces of the ply in the drum circumferential direction while holding each of the end ends of the ply on the separator and joining the end faces to each other; and an inspection step of irradiating light from an illumination unit provided on the separator from the inner side in the drum radial direction onto the joint formed by the joining step and detecting defects in the joint by the transmitted light. This configuration makes it possible to inspect the joint of the ply even when a cylindrical ply is molded so as to overlap the outer side of the band-shaped rubber member in the drum radial direction.

[0008] According to one embodiment of the present disclosure, there is provided a ply joint inspection method as described in (2) above, wherein the inspection step detects defects in the joint by capturing an image of the joint, which is irradiated with light from the inner side in the drum radial direction, from the outer side in the drum radial direction. This configuration makes it possible to easily inspect the ply joint.

[0009] According to one embodiment of the present disclosure, there is provided a ply joint inspection method as described in (3) above, wherein the inspection step includes pulling the separator out of the building drum in the drum axial direction and varying the imaging position of the joint in accordance with the change in the position where the light is irradiated due to the pulling out of the separator. This configuration allows inspection of the ply joint and collection of the separator to be performed simultaneously.

[0010] According to one embodiment of the present disclosure, there is provided a ply bond inspection method as described in (4) above, wherein the inspection step includes pulling the separator out of the building drum in the drum axial direction while suctioning the both end portions of the ply and restricting movement of the both end portions in the drum axial direction. This configuration makes it possible to prevent the position of the ply from shifting relative to the belt-shaped rubber member when the separator is pulled out.

[0011] According to one embodiment of the present disclosure, there is provided a ply bond inspection method as described in any one of (1) to (4), wherein the separator placement step moves the separator in the drum axial direction relative to the building drum while suctioning the separator and restricting movement of the separator in the drum radial direction. This configuration makes it possible to prevent the separator from damaging the belt-shaped rubber member when the separator moves.

[0012] A ply bond inspection method according to one embodiment of the present disclosure is (6) the ply bond inspection method according to any one of (1) to (5), wherein, in the ply winding step, one end of the ply is held by suction on the separator while the ply is wound around the outer circumferential surface of the building drum, and then the other end is held by suction on the separator. This configuration allows the ply winding step to be performed efficiently.

[0013] According to one embodiment of the present disclosure, there is provided a ply joint inspection method (7) according to any one of (1) to (6), wherein in the joining step, the end faces of the ply are joined along the drum axial direction while the end ends of the ply are attracted to each other and movement of the end ends in the drum axial direction is restricted. This configuration makes it possible to prevent the end ends of the ply from shifting in position in the drum circumferential direction during the joining step, thereby preventing a decrease in ply joint accuracy.

[0014] A ply bond inspection method according to one embodiment of the present disclosure is (8) the ply bond inspection method according to any one of (1) to (7), further comprising, before the separator placement step, a drum deformation step of retracting a portion of the outer peripheral surface of the building drum in the drum circumferential direction inward in the drum radial direction to form a space in which the separator can be placed. This configuration makes it possible to prevent the separator placed in the separator placement step from protruding outward in the drum radial direction.

[0015] A ply joint inspection device according to a second aspect of the present disclosure is (9) a ply joint inspection device comprising: a building drum on whose outer peripheral surface a band-shaped rubber member can be wound; a separator disposed between the band-shaped rubber member and the ply, with the ply wound along the outer peripheral surface of the building drum so as to cover the outer radial side of the band-shaped rubber member wound on the outer peripheral surface of the drum; and an inspection device capable of detecting defects in a joint where both end faces of the ply in the drum circumferential direction are butted together, wherein the separator has an illumination unit capable of irradiating light onto the joint from the inner radial side of the drum, and the inspection device is capable of detecting defects in the joint by light from the illumination unit that passes through the joint. With this configuration, inspection of the joint of the ply can be realized even when a cylindrical ply is molded so as to overlap the outer radial side of the band-shaped rubber member.

[0016] According to one embodiment of the present disclosure, there is provided a ply joint inspection device as described in (10) above, wherein the inspection device is capable of detecting defects in the joint by capturing an image of the joint, which is irradiated with light from the inside in the drum radial direction, from the outside in the drum radial direction. This configuration makes it possible to easily inspect the ply joint.

[0017] According to an embodiment of the present disclosure, there is provided a ply bond inspection device as described in (10) above, wherein the inspection device is capable of varying an imaging position of the bond in the drum axial direction. This configuration allows inspection of the ply bond and collection of the separator to be performed simultaneously.

[0018] According to one embodiment of the present disclosure, there is provided a ply joint inspection device as set forth in any one of (9) to (11), further comprising a suction device configured to suction both end portions of the ply and restrict movement of the both end portions in the drum axial direction. This configuration makes it possible to prevent the position of the ply from shifting relative to the belt-shaped rubber member during the joining process and the inspection process.

[0019] According to an embodiment of the present disclosure, there is provided a ply bond inspection device as described in (12) above, wherein the suction device is capable of moving in the drum axial direction relative to the building drum while suctioning the separator and restricting movement of the separator in the drum radial direction. This configuration makes it possible to prevent the separator from damaging the belt-shaped rubber member when moving the separator in the separator placement step.

[0020] According to one embodiment of the present disclosure, there is provided a ply bond inspection device as set forth in any one of (9) to (13), wherein the separator has suction ports capable of sucking both end portions of the ply. With this configuration, both end portions of the ply in the drum circumferential direction can be securely held by the separator.

[0021] According to one embodiment of the present disclosure, there is provided a ply bond inspection device as set forth in any one of (9) to (14), wherein the building drum is configured to retract a portion of the outer peripheral surface of the drum in the drum circumferential direction inward in the drum radial direction to form a space in which the separator can be disposed. This configuration prevents the separator disposed in the separator disposing step from protruding outward in the drum radial direction.

[0022] A ply bond inspection device according to one embodiment of the present disclosure is (16) the ply bond inspection device according to any one of (9) to (15) above, including a joining device capable of butting together and joining the end faces of the ply while the end ends are held on the separator. With this configuration, the joining process can be performed.

[0023] According to the present disclosure, it is possible to provide a ply joint inspection method and a ply joint inspection device that can inspect the joints of plies even when a cylindrical ply is molded so as to be overlapped on the radial outside of another cylindrical member.

[0024] 4A is a diagram showing a ply bond inspection device according to an embodiment of the present disclosure; FIG. 4B is a diagram showing a portion of a cross section perpendicular to the drum axial direction of the building drum shown in FIG. 1; FIG. 4C is a diagram showing a portion of a cross section perpendicular to the drum axial direction of the building drum shown in FIG. 4D; FIG. 4E is a diagram showing a portion of a cross section perpendicular to the drum axial direction of the building drum shown in FIG. 4F; FIG. 4G is a diagram showing a portion of a cross section perpendicular to the drum axial direction of the building drum shown in FIG. 4G.

[0025] Hereinafter, embodiments of a ply bond inspection method and a ply bond inspection device according to the present disclosure will be described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals.

[0026] 1 is a diagram showing a ply bond inspection device 1 as one embodiment of the ply bond inspection device according to the present disclosure. The ply bond inspection device 1 is used to mold a cylindrical component for a pneumatic tire in which a band-shaped rubber member X and a ply Y are overlapped in the radial direction. Examples of the band-shaped rubber member X include tire materials such as an inner liner and side rubber. Examples of the ply Y include a carcass ply as a tire material formed by covering a reinforcing cord with rubber.

[0027] 1 , the ply bond inspection device 1 of this embodiment includes an apparatus main body 10 and a building drum 80. The apparatus main body 10 includes a separator 20, an inspection device 40, a bonding device 30, a suction device 50, a separator drive unit 60, a bond inspection drive unit 61, and a control unit 70.

[0028] Hereinafter, for the sake of convenience, the direction parallel to the central axis O of the building drum 80 will be referred to as the "drum axial direction A." Furthermore, the direction around the central axis O of the building drum 80 will be referred to as the "drum circumferential direction B." Furthermore, the radial direction of the circle around the central axis O of the building drum 80 will be referred to as the "drum radial direction C." Furthermore, the outer surface of the building drum 80 in the drum radial direction C will be referred to as the "drum outer peripheral surface 88."

[0029] 1, in the ply bond inspection device 1 of this embodiment, the device main body 10 and the building drum 80 are arranged side by side in the drum axial direction A. For convenience of explanation, hereinafter, in the drum axial direction A, one side (the right side in FIG. 1) on which the building drum 80 is located may be referred to as the "rear side A1," and the other side (the left side in FIG. 1) on which the device main body 10 is located may be referred to as the "front side A2."

[0030] Fig. 2 is a diagram showing a portion of a cross section perpendicular to the drum axial direction A of the building drum 80. Fig. 3 is a flowchart showing a ply joint inspection method performed using the ply joint inspection device 1. Figs. 4A to 4G are schematic diagrams showing an overview of each step in the ply joint inspection method shown in Fig. 3 performed using the ply joint inspection device 1. Figs. 5A to 5G are diagrams showing a portion of a cross section perpendicular to the drum axial direction A of the building drum 80 shown in Figs. 4A to 4G.

[0031] 4A and 5A, the building drum 80 is capable of winding a belt-shaped rubber member X onto a drum outer peripheral surface 88. As shown in Fig. 5A, an inner liner X1 and side rubber X2 as the belt-shaped rubber member X are wound onto the drum outer peripheral surface 88 of the building drum 80 shown in this embodiment. In other words, the building drum 80 of this embodiment is a tire building drum that is capable of building a green tire before vulcanization by sequentially layering tire materials on the drum outer peripheral surface 88 from the inside to the outside in the drum radial direction C. The drum outer peripheral surface 88 of the building drum 80 of this embodiment is circular or approximately circular when viewed from the drum axial direction A.

[0032] As shown in FIGS. 4B and 5B , the building drum 80 of this embodiment is capable of retracting a portion of the drum outer peripheral surface 88 in the drum circumferential direction B inward in the drum radial direction C. More specifically, as shown in FIGS. 2 and 5A to 5G , the building drum 80 of this embodiment includes a plurality of segments 81 whose outer surfaces in the drum radial direction C form the drum outer peripheral surface 88. In other words, the outer peripheral surfaces of the plurality of segments 81 collectively form a single drum outer peripheral surface 88. As shown in FIGS. 2 and 5A to 5G , the plurality of segments 81 include partial expansion / contraction segments 81 a that can retract inward in the drum radial direction C relative to adjacent segments 81 in the drum circumferential direction B, thereby forming a retracted surface 88 a in a portion of the drum outer peripheral surface 88 in the drum circumferential direction B. Furthermore, as shown in FIGS. 2 and 5A to 5G , the building drum 80 of this embodiment is equipped with a drum deformation drive unit 85 that can retract the partial expansion / contraction segments 81 a inward in the drum radial direction C. That is, the forming drum 80 of this embodiment can cause a portion of the drum outer circumferential surface 88 in the drum circumferential direction B to retract inward in the drum radial direction C by driving the drum deformation drive unit 85 to cause the partial expansion / contraction segment 81 a to retract inward in the drum radial direction C. As shown in FIGS. 4G and 5G , the forming drum 80 of this embodiment can cause a portion of the drum outer circumferential surface 88 in the drum circumferential direction B to retract inward in the drum radial direction C, and then advance the portion of the drum outer circumferential surface 88 in the drum circumferential direction B outward in the drum radial direction C. More specifically, with the portion of the drum outer circumferential surface 88 in the drum circumferential direction B retracted, the drum deformation drive unit 85 can be driven to advance the partial expansion / contraction segment 81 a outward in the drum radial direction C, thereby advancing the portion of the drum outer circumferential surface 88 in the drum circumferential direction B outward in the drum radial direction C.

[0033] 2 and 5A to 5G, suction ports 82 are formed on the outer surface of the partial expansion / contraction segment 81a in the drum radial direction C. A plurality of suction ports 82 are arranged at intervals in the drum axial direction A on the outer surface of the partial expansion / contraction segment 81a in the drum radial direction C. The suction ports 82 can suck the belt-shaped rubber member X wound around the outer peripheral surface 88 of the building drum 80 inward in the drum radial direction C by driving an external device such as a suction pump connected to the building drum 80. This allows the belt-shaped rubber member X wound around the outer peripheral surface 88 of the building drum 80 to be adsorbed onto the outer surface of the partial expansion / contraction segment 81a in the drum radial direction C.

[0034] <Separator 20> As shown in FIGS. 1 and 4A to 4G , the separator 20 extends in the drum axial direction A. The separator 20 is disposed between the belt-shaped rubber member X and the ply Y, with the ply Y being wound along the drum outer peripheral surface 88 of the building drum 80 so as to cover the outer side in the drum radial direction C of the belt-shaped rubber member X wound around the drum outer peripheral surface 88 (see FIGS. 4D to 4F and 5D to 5F ). ​​Also, as shown in FIG. 5C , the separator 20 is disposed in a portion of the drum circumferential direction B on the outer side in the drum radial direction C of the belt-shaped rubber member X wound around the drum outer peripheral surface 88 of the building drum 80 by a separator disposing step S3, which will be described later. Hereinafter, for convenience of explanation, the position in the drum circumferential direction B where the separator 20 is disposed in the separator disposing step S3, which will be described later, may be referred to as the "ply holding position."

[0035] 5D and 5E , when the separator 20 is disposed in the ply holding position, it can hold both ends y1, y2 in the drum circumferential direction B of the ply Y wound around the outer circumferential surface 88 of the building drum 80. More specifically, when the separator 20 is disposed in the ply holding position, it has a ply holding surface 25 facing outward in the drum radial direction C, and both ends y1, y2 of the ply Y in the drum circumferential direction B are supported and held by the ply holding surface 25 from the inside in the drum radial direction C.

[0036] 5C to 5F , the separator 20 of this embodiment has a mechanism that, when positioned in the ply holding position, can suck both ends y1 and y2 of the ply Y in the drum circumferential direction B wound around the outer peripheral surface 88 of the building drum 80 inward in the drum radial direction C. More specifically, the separator 20 of this embodiment has a connection port that can be connected to an external device such as a suction pump or to a vacuum pipe of the building drum 80 that can be connected to an external device such as a suction pump, and a suction port 23 that communicates with the connection port. A plurality of suction ports 23 are formed on the ply holding surface 25 at intervals in the drum axial direction A. The suction ports 23 can be driven by an external device such as a suction pump to suck both ends y1 and y2 of the ply Y in the drum circumferential direction B positioned on the ply holding surface 25 inward in the drum radial direction C. This allows both ends y1 and y2 of the ply Y in the drum circumferential direction B to be securely held on the ply holding surface 25 of the separator 20.

[0037] The separator 20 may have any configuration as long as it has a mechanism capable of sucking each of the end portions y1 and y2 of the ply Y in the drum circumferential direction B toward the inside in the drum radial direction C, and is not limited to a configuration having the suction ports 23. Specifically, the separator 20 may have a configuration capable of sucking each of the end portions y1 and y2 of the ply Y in the drum circumferential direction B by magnetic force, for example.

[0038] 4C and 5C , in a separator placement step S3 (described later), the separator 20 is placed in a space formed by retracting a portion of the drum outer circumferential surface 88 of the building drum 80 in a drum deformation step S2 (described later). In other words, the ply holding position is a position that is inward in the drum radial direction C from the drum outer circumferential surface 88 (see FIG. 5A ) before the retracted surface 88 a is formed on the drum outer circumferential surface 88 of the building drum 80, and where the retracted surface 88 a is located in the drum circumferential direction B. As shown in FIG. 5C , when the separator 20 of this embodiment is placed at such a ply holding position, its outer surface in the drum radial direction C (the ply holding surface 25 in this embodiment) is positioned so as to substantially coincide with the position of the drum outer circumferential surface 88 (see FIG. 5A ) of the building drum 80 before the retracted surface 88 a is formed. More specifically, when the separator 20 of this embodiment is arranged in the ply holding position, the outer surface in the drum radial direction C (the ply holding surface 25 in this embodiment) has a curved surface that is convex outward in the drum radial direction C so that the outer surface thereof substantially coincides with the position of the drum outer circumferential surface 88 (see FIG. 5A ) of the building drum 80 before the receding surface 88 a is formed. This allows the shape of the ply Y when viewed from the drum axial direction A to approach a perfect circle when the ply Y is wound around the drum outer circumferential surface 88 of the building drum 80 to cover the separator 20 in the ply winding step S4 described below.

[0039] As shown in Figures 5C to 5F, the separator 20, when disposed in the ply holding position, includes an illumination unit 21 capable of irradiating light outward in the drum radial direction C. By including such an illumination unit 21, light can be irradiated from the inside in the drum radial direction C to the joint portion Ya of the ply Y joined in the joining process S5, which will be described later. As shown in Figures 1 and 4A to 4G, the separator 20 of this embodiment is configured so that the illumination unit 21 is located at the end of the rear side A1 in the drum axial direction A. As an example, the illumination unit 21 of this embodiment is configured by a light-emitting diode provided on the ply holding surface 25. However, the configuration of the illumination unit 21 is not limited thereto as long as it can irradiate light to the joint portion Ya of the ply Y from the inside in the drum radial direction C.

[0040] In this embodiment, the separator 20 has an end portion on the rear side A1 in the drum axial direction A that can be attracted by magnetic force. More specifically, as shown in Figures 1 and 4A to 4G, the separator 20 of this embodiment has an attractable portion 22 made of a magnetic material such as steel at the end position on the rear side A1 in the drum axial direction A. This allows the end portion on the rear side A1 of the separator 20 in the drum axial direction A to be attracted by an attraction device 50, which will be described later.

[0041] The material for forming the separator 20 is not particularly limited, but it is preferably formed from a hard material such as a metal such as aluminum or stainless steel, or a resin. In addition, in order to reduce the sliding resistance with the ply Y that occurs when the separator 20 is pulled out in the inspection step S6 described below, it is preferable that the surface of the separator 20 is polished, coated, or the like to have a surface property that makes it difficult for the separator 20 to adhere to the ply Y.

[0042] As shown in FIGS. 1 and 4A to 4G , the building drum 80 of this embodiment is provided with a separator guide 90. The separator guide 90 is used to guide the separator 20, which moves in the drum axial direction A in the separator placement step S3 described below, to a separator holding position. More specifically, as shown in FIGS. 1 and 4A to 4G , the separator guide 90 of this embodiment includes a first guide portion 90a disposed at the end of the front side A2 of the building drum 80 in the drum axial direction A, and a second guide portion 90b disposed at the end of the rear side A1 of the building drum 80 in the drum axial direction A. As shown in FIGS. 1 and 4A to 4G , the first guide portion 90a has a guide gap penetrating in the drum axial direction A. The separator 20 can be inserted into the guide gap. The guide gap restricts movement of the separator 20 inserted into the guide gap in the drum radial direction C and the drum circumferential direction B, while allowing movement in the drum axial direction A. As shown in FIGS. 1 and 4A to 4G , the second guide portion 90b has a guide recess recessed toward the rear side A1 in the drum axial direction A. As shown in FIGS. 4D and 4E , the guide recess can accommodate the rear side A1 end of the separator 20 positioned at the ply holding position. With the rear side A1 end of the separator 20 positioned at the ply holding position accommodated in the guide recess, the guide recess restricts movement of the separator 20 in the drum radial direction C and the drum circumferential direction B, as well as movement toward the rear side A1 in the drum axial direction A. Providing such a separator guide 90 allows the separator 20 to be efficiently positioned at the ply holding position in the separator positioning step S3, which will be described later. The configuration of the separator guide 90 is not limited to the above, as long as it can guide the separator 20 to the ply holding position.

[0043] As shown in FIGS. 1 and 4A to 4G, the building drum 80 of this embodiment is provided with a separator lock 91. The separator lock 91 is movable between a locked position (see FIGS. 4D and 4E) and an unlocked position (see FIGS. 4A to 4C, 4F, and 4G). When in the locked position, the separator lock 91 fixes the separator 20 in the ply holding position, whereas when in the unlocked position, the separator lock 91 releases the separator 20 from the fixed position. More specifically, when in the locked position, the separator lock 91 of this embodiment biases the separator 20, which is positioned in the ply holding position, toward the rear side A1 in the drum axial direction A and presses it against the inner surface of the guide recess of the second guide portion 90b of the separator guide 90. This fixes the separator 20 in the ply holding position. On the other hand, when in the unlocked position, the separator lock 91 of this embodiment does not bias the separator 20 toward the rear side A1 in the drum axial direction A, and releases the separator 20 from the fixed position. By providing such a separator lock 91, it is possible to selectively fix and release the separator 20 to and from the ply holding position. The configuration of the separator lock 91 is not limited to the above, as long as it is possible to selectively fix and release the separator 20 to and from the ply holding position.

[0044] In the ply bond inspection device 1 of this embodiment, the separator 20 is fixed at the ply holding position by the separator lock 91, and is thereby connected to the vacuum piping of the building drum 80. In this state, by driving an external device such as a suction pump connected to this vacuum piping, both end portions y1 and y2 of the ply Y located on the ply holding surface 25 can be sucked through the suction ports 23 of the separator 20.

[0045] <Joining Device 30> The joining device 30 can butt and join both end faces y1, y2 of the ply Y in the drum circumferential direction B while the end faces y1, y2 are held on the separator 20. More specifically, as shown in FIG. 5E , the joining device 30 of this embodiment includes a zipper portion 31 having a pair of joint rollers 32. The joining device 30 of this embodiment brings the pair of joint rollers 32 into contact with both end faces y1, y2 of the ply Y in the drum circumferential direction B, respectively, and moves the zipper portion 31 along the drum axial direction A while rotating the joint rollers 32, thereby drawing both end faces y1, y2 of the ply Y in the drum circumferential direction B closer to each other and butting and joining the end faces of the both end faces y1, y2 (see FIGS. 4E and 5E ). As described above, the joining device 30 of this embodiment is configured to include a zipper portion 31 having a pair of joint rollers 32, but the configuration of the joining device 30 is not limited to the above as long as it is possible to join the end faces y1, y2 of the ply Y in the drum circumferential direction B by butting them together.

[0046] <Inspection Device 40> The inspection device 40 can detect defects in the joint Ya of the ply Y, which is formed by butting together the end faces y1, y2 of the ply Y in the drum circumferential direction B. Specifically, the inspection device 40 can detect defects in the joint Ya of the ply Y by transmitting light from the illumination unit 21 that passes through the joint Ya of the ply Y. As shown in FIGS. 4F and 5F , the inspection device 40 of this embodiment can image the joint Ya of the ply Y, which is irradiated with light from the inside in the drum radial direction C, from the outside in the drum radial direction C. As shown in FIG. 4F , the inspection device 40 of this embodiment can change the imaging position of the joint Ya of the ply Y in the drum axial direction A. The inspection device 40 of this embodiment is, for example, configured with a digital camera capable of capturing images attached to a joint inspection drive unit 61 (described later). However, the configuration of the inspection device 40 is not limited to the above, as long as it can image the joint Ya of the ply Y, which is irradiated with light from the inside in the drum radial direction C, from the outside in the drum radial direction C.

[0047] <Suction Device 50> As shown in FIGS. 1 and 4A to 4G, the suction device 50 of this embodiment includes a suction hand 51 and a suction drive unit 52. The suction hand 51 is configured to generate electromagnetic force and can attract magnetic materials. As will be described in detail later, in the ply bond inspection method of this embodiment, the suction hand 51 can attract a carcass ply (ply Y) containing a reinforcing cord made of a magnetic material such as steel therein, and an attractable portion 22 of a separator 20 formed of a magnetic material such as steel. The suction drive unit 52 is connected to the suction hand 51 and moves the suction hand 51 in the drum axial direction A and the drum radial direction C. However, the configuration of the suction device 50 is not limited to the above. For example, the suction hand 51 may have a suction port connected to an external device such as a suction pump and be capable of attracting the ply Y and the separator 20 by suction through the suction port.

[0048] <Separator driving unit 60, bonding inspection driving unit 61, control unit 70> The separator driving unit 60 is detachably connected to the separator 20. The separator driving unit 60 can move the separator 20 in the drum axial direction A. The bonding inspection driving unit 61 is connected to the inspection device 40 and the bonding device 30. The bonding inspection driving unit 61 can move the inspection device 40 and the bonding device 30 in the drum axial direction A and can also move the inspection device 40 and the bonding device 30 separately in the drum radial direction C. The control unit 70 controls the suction driving unit 52, the bonding inspection driving unit 61, and the separator driving unit 60 to control the direction, speed, and amount of movement of the bonding device 30, the inspection device 40, the suction device 50, and the separator 20. The control unit 70 includes, for example, a general-purpose processor such as a CPU (central processing unit) or an MPU (micro processing unit), or a dedicated processor specialized for specific processing. The control unit 70 may further include a storage unit such as a ROM (read only memory) or a RAM (random access memory).

[0049] The following describes a ply joint inspection method performed using the above-described ply joint inspection device 1. As shown in Figure 3, the ply joint inspection method performed using the ply joint inspection device 1 includes a rubber member winding step S1, a drum deformation step S2, a separator placement step S3, a ply winding step S4, a joining step S5, an inspection step S6, and an integration step S7. Each of steps S1 to S7 will be described in detail below.

[0050] 4A and 5A , in the rubber member winding step S1, a belt-shaped rubber member X is wound around the drum outer circumferential surface 88 of the building drum 80. More specifically, as shown in Fig. 4A and 5A , in the rubber member winding step S1 of this embodiment, an inner liner X1 and a side rubber X2 as the belt-shaped rubber member X are wound in this order around the drum outer circumferential surface 88 of the building drum 80 to form a cylindrical shape.

[0051] <Drum Deforming Step S2> As shown in FIGS. 4B and 5B , in the drum deforming step S2, after the rubber member winding step S1, a portion of the drum outer peripheral surface 88 of the building drum 80 in the drum circumferential direction B is retracted inward in the drum radial direction C to form a space in which the separator 20 can be disposed. More specifically, in the drum deforming step S2 of this embodiment, the drum deformation drive unit 85 is driven to retract the partial expansion / contraction segment 81 a inward in the drum radial direction C, thereby retracting a portion of the drum outer peripheral surface 88 in the drum circumferential direction B in the drum radial direction C, thereby forming a retracted surface 88 a in part of the drum outer peripheral surface 88 in the drum circumferential direction B. By forming the retracted surface 88 a, a space is formed between the retracted surface 88 a and the position of the drum outer peripheral surface 88 (see FIG. 5A , etc.) before the retracted surface 88 a was formed. A separator 20 can be disposed in this space in the separator disposing step S3, which will be described later.

[0052] 4B and 5B , in the drum deformation step S2 of this embodiment, when a portion of the drum outer peripheral surface 88 of the building drum 80 in the drum circumferential direction B is retracted in the drum radial direction C, the belt-shaped rubber member X is first adsorbed to the portion of the drum outer peripheral surface 88 of the building drum 80 in the drum circumferential direction B. More specifically, an external device such as a suction pump connected to the building drum 80 is driven to suck the belt-shaped rubber member X through suction ports 82 provided on the outer surface of the partial expansion / contraction segment 81a in the drum radial direction C that forms the retraction surface 88a (see FIG. 5B ). As a result, the belt-shaped rubber member X is adsorbed to the outer surface of the partial expansion / contraction segment 81a in the drum radial direction C. In this state, by retracting the partial expansion / contraction segment 81a inward in the drum radial direction C, the portion of the belt-shaped rubber member X in the drum circumferential direction B can be retracted inward in the drum radial direction C together with the partial expansion / contraction segment 81a. As a result, when a portion of the drum circumferential direction B of the drum outer surface 88 of the building drum 80 is retracted inward in the drum radial direction C, the band-shaped rubber member X remains in the ply holding position, preventing the placement of the separator 20 from being obstructed in the separator placement process S3 described below.

[0053] 4C and 5C , in the separator arrangement step S3, after the drum deformation step S2, a separator 20 is arranged in a part of the drum circumferential direction B on the outer side of the belt-shaped rubber member X in the drum radial direction C. This allows the belt-shaped rubber member X and the ply Y wound around the outer side of the belt-shaped rubber member X in the drum radial direction C to be separated in the drum radial direction C at the position where the separator 20 is arranged.

[0054] Furthermore, in the separator placement step S3 of this embodiment, the separator 20 is placed in the space formed in the drum deformation step S2. That is, the ply retention position, where the separator 20 is placed, is the position in the drum circumferential direction B where the recessed surface 88a is formed in the drum deformation step S2. By placing the separator 20 in this position, the separator 20 is less likely to protrude outward in the drum radial direction C from the position of the drum outer circumferential surface 88 (see FIG. 5A , etc.) before the recessed surface 88a is formed. As a result, when the ply Y is wound around the drum outer circumferential surface 88 of the building drum 80 to cover the separator 20 in the ply winding step S4 described below, the shape of the ply Y when viewed from the drum axial direction A is more likely to be a perfect circle, thereby improving the quality of the finished pneumatic tire. Conversely, if the drum deformation step S2 is not performed before the separator placement step S3 and the separator 20 is placed without forming the receding surface 88a on the drum outer peripheral surface 88 of the building drum 80, the separator 20 will be placed on the circular or approximately circular drum outer peripheral surface 88 as viewed from the drum axial direction A, so as to protrude outward in the drum radial direction C. If the ply Y is wound around the drum outer peripheral surface 88 of the building drum 80 in this state to cover the separator 20, the shape of the ply Y as viewed from the drum axial direction A will have a part of the drum circumferential direction B protruding outward in the drum radial direction C, reducing the circularity of the ply Y. Therefore, as described above, it is preferable that the separator 20 be placed in the space at the position of the receding surface 88a formed in the drum deformation step S2.

[0055] 4C , in the separator placement step S3 of this embodiment, the separator drive unit 60 is driven to move the separator 20 toward the rear side A1 in the drum axial direction A relative to the building drum 80 and place it at the ply holding position. At this time, the separator 20 is guided to the ply holding position by the first guide portion 90a and the second guide portion 90b of the separator guide 90. Furthermore, once the separator 20 has reached the ply holding position, it is removed from the separator drive unit 60 and fixed at the ply holding position by the separator lock 91 (see FIG. 4D ).

[0056] 4C , in the separator placement step S3 of this embodiment, the suction device 50 suctions the end portion of the separator 20 on the rear side A1 in the drum axis direction A, and the separator 20 is moved toward the rear side A1 in the drum axis direction A relative to the building drum 80 while restricting movement of the end portion of the separator 20 on the rear side A1 in the drum axis direction A in the drum radial direction C. More specifically, the suction drive unit 52 of the suction device 50 is first driven to bring the suction hand 51 into contact with the attractable portion 22 provided at the end portion of the separator 20 on the rear side A1 in the drum axis direction A. Then, while the suction hand 51 is in contact with the attractable portion 22 of the separator 20, an electromagnetic force is generated in the suction hand 51, thereby attracting the attractable portion 22 of the separator 20, which is made of a magnetic material such as steel. This restricts movement of the end portion of the separator 20 on the rear side A1 in the drum axis direction A in the drum radial direction C. While maintaining this restricted state, the separator drive unit 60 and the suction drive unit 52 are driven to move the separator 20 together with the suction hand 51 to the rear side A1 in the drum axial direction A. This prevents the end of the separator 20 on the rear side A1 in the drum axial direction A from bending inward in the drum radial direction C as the separator 20 moves to the rear side A1 in the drum axial direction A, thereby preventing the separator 20 from damaging the belt-shaped rubber member X located inside the separator 20 in the drum radial direction C. Figure 4C shows a state in which the separator 20 is being moved together with the suction hand 51 to the rear side A1 in the drum axial direction A.

[0057] 4D and 5D , in the ply winding step S4, after the separator arrangement step S3, the ply Y is wound so as to cover the outer sides of the belt-shaped rubber member X and the separator 20 in the drum radial direction C. At this time, the winding is performed so that both end portions y1 and y2 of the ply Y in the drum circumferential direction B are held on the separator 20 (see FIG. 5D ). As a result, most of the ply Y in the drum circumferential direction B is wound on the outer surface of the belt-shaped rubber member X in the drum radial direction C, but both end portions y1 and y2 of the ply Y in the drum circumferential direction B are spaced apart from the belt-shaped rubber member X to the outside in the drum radial direction C. As shown in FIG. 5D , in the ply winding step S4 of this embodiment, both end portions y1 and y2 of the ply Y in the drum circumferential direction B are sucked by suction ports 23 provided in the ply holding surface 25 of the separator 20 and are sucked onto the ply holding surface 25 of the separator 20. This allows both ends y1 and y2 of the ply Y in the drum circumferential direction B to be securely held on the separator 20. In the ply winding step S4 of this embodiment, the ply Y is a carcass ply formed by coating reinforcing cords made of a magnetic material such as steel with rubber.

[0058] The ply winding step S4 of this embodiment is performed in the following procedure. First, of both end portions y1 and y2 of the ply Y in the drum circumferential direction B, one end portion y1 is held by suction on the ply holding surface 25 of the separator 20. Then, while holding this end portion y1 on the ply holding surface 25 of the separator 20, the ply Y is wound around the drum outer circumferential surface 88 of the building drum 80. After the ply Y has been wound around the drum outer circumferential surface 88 for approximately one revolution, the other end portion y2 of the ply Y in the drum circumferential direction B is held by suction on the ply holding surface 25 of the separator 20. By following this procedure, the ply winding step S4 can be performed efficiently.

[0059] 5E , in the joining step S5, after the ply winding step S4, both end portions y1 and y2 of the ply Y in the drum circumferential direction B, which have been wound around the outer circumferential surface 88 of the building drum 80, are held on the separator 20, and the joining device 30 is used to butt and join the both end portions y1 and y2 of the ply Y in the drum circumferential direction B. This allows the both end portions y1 and y2 of the ply Y in the drum circumferential direction B to be butted and joined to each other while keeping the both end portions y1 and y2 of the ply Y in the drum circumferential direction B and the belt-shaped rubber member X spaced apart in the drum radial direction C. Conversely, for example, when joining the ply Y with the entire inner surface of the ply Y in the drum radial direction C attached to the belt-shaped rubber member X, an operation may be required to peel the both end portions y1 and y2 of the ply Y in the drum circumferential direction B from the belt-shaped rubber member X, which may reduce efficiency. In this case, the positions of both ends y1, y2 of the ply Y in the drum circumferential direction B may be unstable, which may reduce the accuracy of joining. That is, as in the joining step S5 of this embodiment, by butting together the end faces of both ends y1, y2 of the ply Y in the drum circumferential direction B while holding each of both ends y1, y2 of the ply Y wound around the drum outer peripheral surface 88 of the building drum 80 on the separator 20, the efficiency and accuracy of the joining work can be improved compared to, for example, joining the ply Y in a state where the entire inner surface of the ply Y in the drum radial direction C is attached to the belt-shaped rubber member X.

[0060] As shown in FIG. 4E , in the joining step S5 of this embodiment, the joining device 30 is moved toward the rear side A1 in the drum axial direction A relative to the building drum 80, while gradually joining both end portions y1, y2 of the ply Y in the drum circumferential direction B along the drum axial direction A, thereby forming a joint Ya extending in the drum axial direction A. At this time, as shown in FIG. 4E , in the joining step S5 of this embodiment, the both end portions y1, y2 of the ply Y in the drum circumferential direction B are sucked by the suction device 50, and while restricting the movement of these both end portions y1, y2 in the drum axial direction A, the end faces of each of the both end portions y1, y2 are gradually joined toward the rear side A1 in the drum axial direction A. As a result, when the joining device 30 joins the both end portions y1, y2 of the ply Y in the drum circumferential direction B toward the rear side A1 in the drum axial direction A, the both end portions y1, y2 are pulled in the moving direction of the joining device 30 (to the rear side A1 in the drum axial direction A in this embodiment), which prevents the positions of the both end portions y1, y2 of the ply Y in the drum circumferential direction B from shifting, thereby preventing a decrease in joining accuracy. Figure 4E shows the state in which the joining device 30 is being moved toward the rear side A1 in the drum axial direction A relative to the forming drum 80, while gradually joining both ends y1 and y2 of the ply Y in the drum circumferential direction B toward the rear side A1 in the drum axial direction A.

[0061] <Inspection step S6> The joint Ya formed in the joining step S5 may have holes penetrating in the drum radial direction C. Such holes may reduce the quality of the joint Ya in terms of joining strength, etc. Therefore, in order to ensure the quality of the joint Ya, an inspection step S6 is performed after the joining step S5, in which holes of a predetermined size or larger are detected as defects.

[0062] 4F and 5F , in the inspection step S6, the illuminating unit 21 provided on the separator 20 irradiates the joint Ya, which was joined in the joining step S5, with light from the inside in the drum radial direction C, and defects in the joint Ya of the ply Y are detected by the transmitted light that passes through the joint Ya of the ply Y. More specifically, when light is irradiated onto the joint Ya of the ply Y from the inside in the drum radial direction C, the light passes through holes formed in the joint Ya that penetrate in the drum radial direction C and leaks outward in the drum radial direction C as transmitted light. Defects in the joint Ya are detected by analyzing this transmitted light that leaks outward in the drum radial direction C.

[0063] 4F and 5F , in the inspection step S6 of this embodiment, the joint Ya of the ply Y, which is irradiated with light from the inside in the drum radial direction C, is imaged by the inspection device 40 from the outside in the drum radial direction C, and defects are detected based on the image. By imaging the joint Ya in this way, inspection of the joint Ya of the ply Y can be easily achieved. However, defects may also be detected visually, for example, without imaging by the inspection device 40.

[0064] 4F , in the inspection step S6 of this embodiment, the separator 20 is withdrawn toward the front side A2 in the drum axial direction A relative to the building drum 80. The image capturing position of the joint Ya is shifted in accordance with the shift in the position where light is irradiated due to the withdrawal of the separator 20. More specifically, immediately after the joining step S5, the separator 20 is positioned in the ply holding position. At this time, the illumination unit 21 is positioned substantially coincident with the end of the ply Y on the rear side A1 in the drum axial direction A. In this state, the separator lock 91 is first shifted from the locked position to the unlocked position to release the locked state of the separator 20, and the separator 20 is attached to the separator drive unit 60. The joint inspection drive unit 61 is then driven to move the inspection device 40 to a position where the end of the ply Y on the rear side A1 in the drum axial direction A can be captured. In this state, the illumination unit 21 of the separator 20 starts irradiating the joint Ya with light, and the inspection device 40 starts capturing an image of the joint Ya. Then, while the light is still irradiated onto the joint Ya of the ply Y, the separator driving unit 60 is driven to move the separator 20 toward the front side A2 in the drum axial direction A. At this time, the illumination unit 21 also moves as the separator 20 moves, thereby changing the position at which the light is irradiated onto the joint Ya of the ply Y. Accordingly, the joint inspection driving unit 61 is driven to move the inspection device 40 in accordance with the change in the position at which the light is irradiated, thereby changing the imaging position of the inspection device 40. This allows inspection of the joint Ya of the ply Y to be performed over the entire area in the drum axial direction A. Furthermore, during the inspection process S6, the separator 20 can be removed and collected from between the belt-shaped rubber member X and the ply Y. In other words, according to the inspection process S6 of this embodiment, inspection of the joint Ya of the ply Y and collection of the separator 20 can be performed simultaneously. Figure 4F shows the state in which the separator 20 is being pulled out toward the front side A2 in the drum axial direction A relative to the building drum 80, and the imaging position of the joint Ya is being changed in accordance with the change in the position where light is irradiated due to the pulling out of the separator 20.

[0065] 4F , in the inspection step S6 of this embodiment, both end portions y1 and y2 of the ply Y in the drum circumferential direction B are suctioned by the suction device 50, and the separator 20 is pulled out toward the front side A2 in the drum axial direction A relative to the building drum 80 while restricting movement of the both end portions y1 and y2 in the drum axial direction A. More specifically, the suction drive unit 52 is first driven to bring the suction hands 51 into contact with both end portions y1 and y2 of the ply Y in the drum circumferential direction B. Then, with the suction hands 51 in contact with both end portions y1 and y2 of the ply Y in the drum circumferential direction B, an electromagnetic force is generated in the suction hands 51 to suction the ply Y. This restricts movement of both end portions y1 and y2 of the ply Y in the drum circumferential direction B in the drum axial direction A, which are wound around the outer peripheral surface 88 of the building drum 80. In this state, the separator 20 is pulled out toward the front side A2 in the drum axial direction A relative to the building drum 80. This allows the separator 20 and the ply Y to slide when the separator 20 is pulled out, and the ply Y is pulled in the direction of pulling out the separator 20 (in this embodiment, the front side A2 in the drum axial direction A), thereby preventing the position of the ply Y from shifting relative to the band-shaped rubber member X.

[0066] 4G and 5G , in the integration step S7, the drum deformation drive unit 85 of the building drum 80 is driven to advance the partial expansion / contraction segment 81 a outward in the drum radial direction C, and the belt-shaped rubber member X is pressed against and attached to the inner surface of the ply Y in the drum radial direction C. This allows the belt-shaped rubber member X and the ply Y to be integrated together.

[0067] As described above, according to the ply joint inspection method of the present disclosure, even when the cylindrical ply Y is molded so as to be overlapped on the outside of another cylindrical member (in this embodiment, the inner liner X1 and the side rubber X2 as the belt-shaped rubber member X) in the radial direction (in this embodiment, the drum radial direction C), the lighting unit 21 provided on the separator 20 arranged between the other cylindrical member and the ply Y irradiates light onto the joint Ya of the ply Y from the inside in the drum radial direction C, and defects in the joint Ya of the ply Y through which the light passes can be detected, thereby enabling inspection of the joint Ya of the ply Y.

[0068] The ply bond inspection method and ply bond inspection device according to the present disclosure are not limited to the specific configurations and processes shown in the above-described embodiments, and various modifications, changes, and combinations are possible without departing from the scope of the claims.

[0069] [Contribution to the United Nations-led Sustainable Development Goals (SDGs)] The SDGs have been proposed to realize a sustainable society. One embodiment of the present invention is thought to be a technology that can contribute to "No. 12: Responsible Consumption and Production" and "No. 13: Take concrete action against climate change."

[0070] The present disclosure relates to a ply bond inspection method and a ply bond inspection apparatus.

[0071] 1: Ply bond inspection device, 10: Device main body, 20: Separator, 21: Lighting unit, 22: Suction unit, 23: Suction unit, 25: Ply holding surface, 30: Bonding device, 31: Zipper unit, 32: Joint roller, 40: Inspection device, 50: Suction device, 51: Suction hand, 52: Suction drive unit, 60: Separator drive unit, 61: Bond inspection drive unit, 70: Control unit, 80: Building drum, 81: Segment, 81a: Partial expansion / contraction segment, 82: Suction port, 85: Drum deformation drive unit, 88: Drum outer peripheral surface, 88a: Retraction surface, 90: Separator guide, 90a: First guide unit, 90b: Second guide unit, 91: Separator lock, A: Drum axial direction, A1: Rear side, A2: Front side, B: Drum circumferential direction, C: Drum radial direction, O: Central axis, S1: Rubber member winding process, S2: Drum deformation process, S3: Separator arrangement process, S4: Ply winding process, S5: Joining process, S6: Inspection process, S7: Integration process, X: Band-shaped rubber member, X1: Inner liner, X2: Side rubber, Y: Ply, Ya: Ply joint, y1, y2: Ply end portions in the drum circumferential direction

Claims

1. A ply joint inspection method comprising: a rubber member winding step of winding a band-shaped rubber member onto the outer peripheral surface of a building drum; a separator arrangement step of arranging a separator on a portion of the drum circumferentially outer side of the band-shaped rubber member in the drum radial direction; a ply winding step of winding a ply to cover the outer side of the band-shaped rubber member and the separator in the drum radial direction; a joining step of butting and joining end faces of both end portions of the ply against each other while holding each end portion of the ply on the separator; and an inspection step of irradiating light from an illumination unit provided on the separator from the inside in the drum radial direction onto the joint formed by the joining step, and detecting defects in the joint by the light that passes through the joint.

2. A ply joint inspection method as described in claim 1, wherein in the inspection process, defects in the joint are detected by imaging the joint, to which the light is irradiated from the inside in the drum radial direction, from the outside in the drum radial direction.

3. A ply joint inspection method as described in claim 2, wherein in the inspection process, the separator is pulled out in the drum axial direction relative to the building drum, and the imaging position of the joint is changed in accordance with the change in the position where the light is irradiated due to the pulling out of the separator.

4. A ply joint inspection method as described in claim 3, wherein in the inspection process, the separator is pulled out in the drum axial direction relative to the building drum while adsorbing both ends of the ply and restricting movement of both ends in the drum axial direction.

5. A ply joint inspection method as described in claim 1 or 2, wherein in the separator placement process, the separator is adsorbed and moved in the drum axial direction relative to the building drum while restricting the separator's movement in the drum radial direction.

6. A ply joint inspection method as described in claim 1 or 2, wherein in the ply winding process, one end of the both ends of the ply is adsorbed and held on the separator while the ply is wound around the outer circumferential surface of the building drum, and then the other end is adsorbed and held on the separator.

7. A ply joint inspection method as described in claim 1 or 2, wherein in the joining process, both ends of the ply are sucked and the end faces of both ends are joined along the drum axial direction while restricting movement of both ends in the drum axial direction.

8. A ply joint inspection method as described in claim 1 or 2, which includes a drum deformation process, prior to the separator placement process, in which a portion of the outer peripheral surface of the molding drum in the drum circumferential direction is recessed inward in the drum radial direction to form a space in which the separator can be placed.

9. A ply joint inspection device comprising: a molding drum on whose outer circumferential surface a band-shaped rubber member can be wound; a separator arranged between the band-shaped rubber member and the ply, with the ply wound along the outer circumferential surface of the drum so as to cover the outer radial outside of the band-shaped rubber member wound around the outer circumferential surface of the molding drum; and an inspection device capable of detecting defects in a joint where the end faces of both ends of the ply in the drum circumferential direction are butted together, wherein the separator has an illumination unit capable of irradiating light onto the joint from the inside in the drum radial direction, and the inspection device is capable of detecting defects in the joint by transmitted light from the illumination unit that passes through the joint.

10. A ply joint inspection device as described in claim 9, wherein the inspection device is capable of detecting defects in the joint by imaging the joint to which the light is irradiated from the inside in the drum radial direction, from the outside in the drum radial direction.

11. The ply bond inspection device according to claim 10, wherein the inspection device is capable of varying the imaging position of the bond in the drum axial direction.

12. A ply joint inspection device according to claim 9 or 10, further comprising a suction device capable of suctioning both end portions of the ply and restricting movement of both end portions in the drum axial direction.

13. A ply bond inspection device as described in claim 12, wherein the suction device is capable of moving in the drum axial direction relative to the building drum while suctioning the separator and restricting movement of the separator in the drum radial direction.

14. A ply bond inspection device according to claim 9 or 10, wherein the separator has a mechanism capable of sucking each of the two end portions of the ply.

15. A ply joint inspection device as described in claim 9 or 10, wherein the molding drum is capable of recessing a portion of the drum outer surface in the drum circumferential direction inward in the drum radial direction to form a space in which the separator can be positioned.

16. A ply joint inspection device according to claim 9 or 10, further comprising a joining device capable of butt-joining the end faces of both end portions of the ply while each end portion is held on the separator.

Images