JP2015020366A - Tire molding drum and tire molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire molding drum and a tire molding method in which positioning of a bead lock part and elevation operation of a folding part can be implemented with good accuracy.SOLUTION: A tire molding drum 1 comprises a central axis 2, a screw shaft 3 built-in in the central axis 2, folding parts 7 which move along the central axis 2 through rotation driving of the screw shaft 3 by a motor, bead lock parts 8 which are provided as movable along the central axis 2, and air cylinders 50 and coupling members 52 which connect or release connection of the folding parts 7 and the bead lock parts 8. The bead lock parts 8 are connected with the folding parts 7, both are moved integrally to position the bead lock parts 8 to specified positions, connections between both are released, and the folding parts 7 only are moved so that side parts of a carcass band are folded.

Description

  The present invention relates to a tire molding drum and a tire molding method for forming a green tire from a carcass band.

  In the process of molding the tire, a cylindrical carcass band with a bead core or other member assembled is placed on the outer periphery of the tire molding drum, and the central part of the carcass band bulges in a toroidal shape so that the side of the carcass band is A method of turning back and assembling a tire constituent member such as tread rubber on the outer peripheral side of the carcass band is known.

  Patent Document 1 describes that a pair of left and right sliders 103 are displaced so as to approach and separate by rotating a screw shaft 102 disposed in a central shaft 101 as shown in FIG. Yes. A bead lock portion 104 and a turn-back portion 105 are attached to the slider 103, and the pair of bead lock portions 104 are moved closer to and away from the core body 106 by the approach and separation of the slider 103, and the turn-back portion 105. Are designed to approach and separate. The bead lock unit 104 operates the air cylinder 104a to move the piston to drive the link 104b, and the drive of the link 104b causes the bead lock body 104c to move upward to move the bead core installed in the bead lock body 104c. Lock it. Further, the folding portion 105 operates the air cylinder 105 a to move the folding arm member 105 b toward the core body 106, and the folding roller 105 c attached to the distal end portion of the folding arm member 105 b is moved along the center bladder 107. To move up and down. The operation of folding the side portion of the carcass band is performed by the raising and lowering operation of the folding roller 105c.

However, in such a tire molding drum, since the folding portion 105 is operated by the air cylinder 105a, when the bead lock portion 104 and the folding portion 105 move together in the central axis direction, driving at a constant pressure is performed. Can only be done. Therefore, it is difficult to accurately position the bead lock unit 104 and raise and lower the folding unit 105. Thus, in order to perform these with high accuracy, for example, it is conceivable to attach a separate detection sensor to detect the ascending / descending position of the folded portion 105, but it is technically difficult to attach the detection sensor.
As another method, for example, by driving the folding unit 105 using a servo motor instead of the air cylinder 105a of the conventional apparatus, it is possible to perform the lifting operation without monitoring the lifting operation of the folding unit 105. It is conceivable to perform such as with high accuracy. However, using a servo motor inevitably increases the size and cost of the apparatus.

International Publication No. 2004/012928

  The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to easily detect the raising and lowering operation of the folded portion and to easily control the operation speed without cost. Thus, it is an object to provide a tire molding drum and a tire molding method capable of accurately positioning a bead lock portion and raising and lowering a folded portion.

  A tire molding drum according to the present invention includes a central axis, a bead lock portion provided to be movable along the central axis, and a side of a mounted carcass band that is provided to be movable along the central axis. A folding part that folds back a part, a motor driving part that moves the folding part along the central axis, and the bead lock part connected to the folding part, and the bead lock part is connected to the folding part by the motor driving part. And a connecting portion that is movable along the central axis, and that releases the connection and allows only the folded portion to move along the central axis by the motor driving portion.

  According to the present invention, the raising / lowering operation of the folded portion can be easily detected and the operation speed can be easily controlled. Accordingly, the bead lock portion can be moved and positioned with high accuracy, and the folding portion can be moved up and down with high accuracy.

It is a schematic structure figure showing the section of the upper half which passes along the central axis of the tire molding drum of the embodiment concerning the present invention. FIG. 2 is a schematic configuration diagram similar to FIG. 1, and is a schematic configuration diagram illustrating a state in which the diameter of a core body is increased by approaching a screw member from the state illustrated in FIG. 1. FIG. 3 is a schematic configuration diagram similar to FIG. 1, and is a schematic configuration diagram when the folding member is moved up and down by further approaching the screw member from the state shown in FIG. 2. It is explanatory drawing which shows the shaping | molding process using a tire shaping | molding drum. It is explanatory drawing which shows the shaping | molding process using a tire shaping | molding drum. It is a schematic block diagram regarding the conventional tire molding drum.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 to FIG. 3 are schematic configuration diagrams showing a cross section of the upper half passing through the central axis of the tire molding drum 1 according to the embodiment of the present invention (the same applies to the lower half).
The tire molding drum 1 includes a central shaft 2, a screw shaft 3 that is a drive shaft built in the central shaft 2, and a pair of sleeves 4 that are attached to the central shaft 2 so as to be close to and away from each other in the axial direction. Yes. A slider 5 and a support 6 are attached to each sleeve 4 so as to be movable in the axial direction, and the slider 5 is arranged so as to be outside the support 6. A folding part 7 is mounted on the slider 5, and a bead lock part 8 is mounted on the support 6.

The slider 5 is attached to a screw member 9 that is screwed onto the screw shaft 3. When the screw shaft 3 is driven to rotate by a drive motor (not shown) (for example, an electric motor), the screw member 9 approaches and separates. To move to.
In the present embodiment, the screw shaft 3 and a drive motor that rotationally drives the screw shaft 3 correspond to a motor drive unit. An air cylinder 50 is mounted on the slider 5, and a piston 51 of the air cylinder 50 is connected to the support 6 by a connecting member 52. Here, the air cylinder 50 and the connecting member 52 correspond to the connecting portion, and the piston 51 is set so as to be movable in the axial direction integrally with the support body 6. A brake member 60 is attached to the support 6, and the support 6 is fixed so as not to move with respect to the sleeve 4 by pressing the brake member 60 against the sleeve 4 by a driving device (not shown). Further, the support member 6 is set in a movable state by moving the brake member 60 away from the sleeve 4.

The folding portion 7 has one end portion of an arm member 70 rotatably attached to the upper portion of the slider 5, and a pair of folding rollers 71 are rotatably supported via a swing member 72 at the other end portion. Has been. The swing member 72 is rotatably attached to the other end portion of the arm member 70.
The other end portion of the arm member 70 extends to the bead lock portion 8, and the folding roller 71 is placed on the upper surface of the bead lock body 82. As will be described later, the folding roller 71 moves up and down along the folded portion of the side portion of the carcass band by the turning operation of the arm member 70 to perform the folding operation.

The bead lock unit 8 operates the air cylinder 80 to move the piston to drive the link 81, and the drive of the link 81 moves the bead lock body 82 to expand and contract in the radial direction to move the bead lock body 82. Lock the bead core installed in the.
Between the bead lock portions 8, a core body 10 configured to be expandable and contractable in the radial direction is disposed around the central axis 2. A link mechanism 11 is disposed between the core body 10 and the central shaft 2, and one end of a pair of links of the link mechanism 11 is rotatably attached to the inside of the core body 10. Each end is rotatably attached to the sleeve 4. The pair of sleeves 4 are moved closer to and away from each other in the axial direction by a drive device (not shown), whereby the link mechanism 11 is operated to move the core body 10 in the radial direction. Therefore, by operating the pair of sleeves 4, the core body 10 is moved in the radial direction and the expansion / contraction operation is performed.

  A center bladder 12 made of a reinforced rubber film is disposed on the outer peripheral side of the core body 10 (generally referred to as a core member), and both end portions of the center bladder 12 are bead lock portions 8 disposed on both sides. It is fixed to. The center bladder 12 is set so that the space around the core body 10 is sealed, and is bulged and deformed in a toroidal shape by compressed air supplied from an air supply device (not shown).

FIG. 2 is a schematic configuration diagram illustrating a state in which the diameter of the core body 10 is increased by approaching the screw member 9 from the state illustrated in FIG. 1.
When the air cylinder 80 is driven in the state shown in FIG. 1, the bead lock unit 8 moves so as to expand the bead lock body 82 in the radial direction via the link 81 and performs a bead lock operation. Along with the diameter expansion operation of the bead lock body 82, the folding roller 71 placed on the bead lock body 82 moves so as to expand the diameter in the radial direction as it is.
Next, when the screw shaft 3 is rotated by a drive motor to bring the screw member 9 closer, the sliders 5 move in directions approaching each other. At that time, the cylinder, for example, the air cylinder 50 is driven and the piston 51 is set to be moved to the support 6 side (that is, the cylinder mechanism is locked and connected). The support 6 is set in a state in which the brake member 60 is separated from the sleeve 4 and is movable in the axial direction. Therefore, the support 6 moves in a direction approaching each other together with the slider 5 via the connecting member 52. Then, the bead lock portion 8 in the locked state is moved so as to approach each other, and the bead lock portion 8 is positioned so that the locked bead core is set at a predetermined position in the axial direction, and the movement of the screw member 9 is stopped. To do. Next, the core body 10 is expanded by the link mechanism 11 by operating the sleeve 4 so as to approach. In FIG. 2, since the center bladder 12 is not bulged by the pressurized air, the center bladder 12 is stretched so as to protrude in the radial direction by the core body 10.

FIG. 3 is a schematic configuration diagram in a case where the screw member 9 is further moved closer from the state shown in FIG.
After positioning the bead lock portion 8, the support member 6 is fixed to the sleeve 4 by operating the brake member 60 so as to be in pressure contact with the sleeve 4. The air in the air cylinder 50 is discharged and the piston 51 is set in a free state (that is, the cylinder mechanism is unlocked and the connection is released). Then, the screw shaft 3 is rotationally driven to bring the screw member 9 closer to each other, thereby moving the slider 5 in a direction approaching each other. At this time, the piston 51 is set in a free state, and the support 6 is fixed to the sleeve 4 by the pressure contact of the brake member 60, so that only the slider 5 moves so as to approach each other, and the turn-back portion 7 Moves closer to the center bladder 12. Therefore, the folding roller 71 is pressed toward the center bladder 12 and rises along the folded portion of the side portion of the carcass band, and accordingly, the arm member 70 is rotated to perform the folding operation.

4 and 5 are explanatory views showing a molding process using the tire molding drum 1.
First, as shown in FIG. 4A, a carcass band 200 in which a preset bead 201 preset with a bead core and a bead filler and a carcass assembled with an inner liner, a canvas chafer, and the like is formed into a cylindrical shape is formed on the tire molding drum 1. The center bladder 12 is mounted along the outer periphery.

  Next, as shown in FIG. 4B, the bead lock body 82 of the bead lock portion 8 is moved so as to expand in the radial direction, and the bead lock body 82 is pressed against the preset bead 201 to lock the preset bead 201. Set to. Then, as shown in FIG. 4C, with the left and right preset beads 201 in the locked state, as shown in FIG. 2, the slider 5 is moved so that the left and right bead lock portions 8 are moved together with the support 6. And positioned at a predetermined position. At that time, the central portion 200a of the carcass band 200 between the left and right preset beads 201 is expanded in a toroidal shape by pressurizing and expanding the air in the center bladder 12. The folded portion 200b outside the preset bead 201 of the carcass band 200 remains as it is.

  Next, as shown in FIG. 2, the core body 10 is moved so as to expand in the radial direction by the approach of the left and right sleeves 4. Then, as shown in FIG. 4D, both sides of the core body 10 are set to positions close to the bead lock body 82, and both sides of the core body 10 are brought close to the inner surface of the center bladder 12 so that almost no gap is generated. To do. After setting the core body 10, as shown in FIG. 3, the support member 6 is fixed by pressing the brake member 60 against the sleeve 4, and the bead lock portion 8 is set not to move in the axial direction.

Then, as shown in FIG. 5A, the folding portion 7 is operated so that the folded portion 200b outside the preset bead 201 of the carcass band 200 is folded by the preset bead 201 and overlapped with the central portion 200a.
Next, as shown in FIG. 3, the screw member 9 is moved to move only the slider 5 so as to approach each other, and the arm member 70 is rotated so as to push out toward the center bladder 12. 71 moves so as to travel along the preset bead 201 and the core body 10 of the carcass band 200. Therefore, the carcass band can be folded back tightly and bead fastening can be performed satisfactorily, and the folded-back portion 200b can be securely overlapped and crimped to the central portion 200a. For crimping the overlapped portions, the end portions of the folded portions 200b can be pressed and crimped with a stitching roller so that they can be crimped reliably.

  After crimping the folded portion 200b, the sliders 5 are moved away from each other, and the folded portion 7 is returned to the original position and separated from the carcass band. Further, the brake member 60 of the support 6 is released, and the air cylinder 50 is operated to set the slider 5 and the support 6 to the connected state. Then, the sleeve 4 is moved in a direction approaching each other, and as shown in FIG. At this time, the inside of the center bladder 12 is depressurized, so that the core body 10 is smoothly expanded in diameter, and the center portion 200a is set in a state of being in contact with the core body 10.

  Next, as shown in FIG. 5C, a belt member 202 having two or more layers is assembled to the outer periphery of the central portion 200a of the carcass band, and a belt reinforcing member (not shown) such as a spiral layer is assembled as necessary. The tread rubber 203 is assembled to the body. Then, as shown in FIG. 5D, a side wall rubber 204 and a rubber chafer 205 are assembled to the side surface of the carcass band whose side portions are folded back to form a green tire.

As described above, according to the present embodiment, the following operational effects can be obtained.
(I) By moving the support body 6 on which the bead lock portion 8 is mounted and the slider 5 on which the folded portion 7 is mounted, the bead lock portion 8 can be accurately positioned.

(Ii) After the bead lock portion 8 is positioned and fixed to the sleeve 4, the connection state between the support 6 and the slider 5 is released, and only the slider 5 is moved to move the folding portion 7 up and down. Therefore, the raising / lowering operation can be accurately controlled.
That is, the arm member 70 is operated by the drive motor through the slider 5 throughout the entire operation period. Therefore, for example, the position of the arm member 70 (and hence the position of the folding roller 71 on the folded carcass band 200) can be easily detected from the rotational speed of the drive motor, for example. In addition, by using the drive motor, the folding roller 71 can perform an operation control (speed control) such as a folding operation at a low speed at the base portion of the folding portion of the carcass band 200 and a high-speed folding operation from the middle. Such an effect cannot be obtained by a conventional arm drive mechanism using an air cylinder.
(Iii) Since the positioning of the bead lock unit 8 and the raising / lowering operation of the folding unit 7 can be performed by one driving unit, it is possible to save space and reduce costs.

In the above-described embodiment, an air cylinder is used as a connecting portion between the support 6 and the slider 5, but a mechanism other than the air cylinder can be used as long as it has a function of releasing the connection.
In the above description, the tire molding drum has been described as having a structure including a center bladder and a core member, but the tire molding drum of the present invention is not limited to this. That is, the tire molding drum is, for example, a core drum or a bladderless drum (a drum that bulges the carcass band in a toroidal shape while supplying air directly to the space inside the carcass band without using a bladder; No. 293793, etc.), and any kind of drum can be used as long as the carcass band can be folded back.

  DESCRIPTION OF SYMBOLS 1 ... Tire molding drum, 2 ... Center axis, 3 ... Screw axis, 4 ... Sleeve, 5 ... Slider, 6 ... Support body, 7 ... Folding part, 8 ..Bead lock part, 9 ... Screw member, 10 ... Core body, 11 ... Link mechanism, 12 ... Center bladder, 50, 80 ... Air cylinder, 51 ... Piston, 52 ... Connection member, 60 ... Brake member.

Claims (5)

  A central axis, a bead lock portion provided to be movable along the central axis, a folding portion provided to be movable along the central axis, and configured to fold back a side portion of the mounted carcass band; A motor drive unit that moves a portion along the central axis, and the bead lock portion is connected to the folded portion, and the bead lock portion can be moved along the central axis together with the folded portion by the motor drive portion. And a connecting part that releases the connection and allows the motor drive part to move only the folded part along the central axis. In the tire molding drum described in claim 1,
The bead lock portion and the folded portion are respectively mounted on a support body and a slider that are movably disposed along the central axis, and are connected releasably by the connecting portion. In the tire molding drum described in claim 2,
The connecting portion includes a cylinder mechanism, and performs the connection by locking the cylinder mechanism, and releases the connection by releasing the lock of the cylinder mechanism. In the tire molding drum according to any one of claims 1 to 3,
A tire molding drum provided with a brake member fixed to a sleeve movable along the central axis so that the bead lock portion does not move along the central axis. A tire molding method for molding using the tire molding drum according to any one of claims 1 to 4,
The bead lock portion is set in a locked state with respect to the bead core, the bead lock portion is connected to the folded portion, the bead lock portion and the folded portion are moved by the motor driving portion, and the bead lock portion is set to a predetermined position. A tire molding method including each step of positioning at a position, releasing the connection between the bead lock portion and the folded portion, moving only the folded portion by the motor driving portion, and folding the side portion of the carcass band.

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