JP2012236361A - Rigid core holding structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely and efficiently perform the working of transferring a rigid core between devices.SOLUTION: The rigid core is held to be transferred between a holding shaft of a first device and that of a second device. The rigid core includes: a core body comprising a plurality of core segments to be divided in the circumferential direction of a tire; a cylindrical core which is inserted into a center hole of the core body to hinder each of the core segments from being moved to the inside in the radial direction; and a pair of side plates which are disposed on both sides of the core body in the axial direction to hinder each of the core segments from being moved to the axial direction. A supporting shaft projecting into the outside in the axial direction is arranged on each of the side plates. The supporting shafts and the holding shafts are attached/detached freely by a coupling means having a ball locking mechanism.

Description

  The present invention relates to a rigid core holding structure capable of efficiently passing a rigid core between a plurality of devices.

  In recent years, in order to improve the formation accuracy of a pneumatic tire, a rigid core a having an outer shape corresponding to the tire inner surface shape of a vulcanized finished tire is used as shown in FIG. A tire constituent member such as an inner liner, a carcass ply, a belt ply, a sidewall rubber, and a tread rubber is sequentially attached on a to form an unvulcanized tire t, and the unvulcanized tire t is attached to a rigid core a And a method for vulcanizing and molding a pneumatic tire between a rigid core a that is an inner mold and a vulcanization mold b that is an outer mold has been proposed (for example, patents). Reference 1).

  Therefore, in such a tire forming method, the rigid core a is divided into, for example, an inner liner attaching device, a carcass ply attaching device, a belt ply attaching device, a sidewall rubber attaching device, a tread rubber attaching device, a vulcanizing device, and the like. It is necessary to sequentially transfer between these devices and perform a pasting operation, a vulcanizing operation, and the like of each tire constituent member.

  On the other hand, the rigid core a needs to be disassembled and removed from the lumen of the pneumatic tire after vulcanization molding. Therefore, as shown in FIG. It is formed from a plurality of core segments c divided in the direction. Specifically, the first core segment c1 in which the dividing surfaces at both ends in the circumferential direction are inclined in the direction in which the circumferential width decreases toward the inner side in the radial direction, and the first core segment c1 are alternately arranged in the circumferential direction. And the split surfaces at both ends in the circumferential direction are inclined inward in the radial direction so as to increase in the circumferential width, and the radius is sequentially increased from the second core segment c2. It can be removed from the vulcanized tire by moving it one by one inward.

  Each core segment c is assembled into an annular shape by bolting the inner end in the radial direction to the core portion d1 of the frame d having an annular core portion d1. In the frame d, the one end side of the core part d1 is opened, so that the bolt e can be attached and detached from the opening f.

  However, in this case, since the support shaft portion g for supporting the rigid core a can be provided only on one side of the frame d, the delivery operation of the rigid core a between the devices becomes complicated, and the rigid The attachment accuracy of the child a was impaired and the working efficiency was significantly reduced.

  Patent Document 2 below proposes a tire-forming drum connecting structure that shortens the time for exchanging the tire-forming drum and improves the efficiency of the tire manufacturing operation. However, this has a complicated structure and a problem that the handling ability of the rigid core a is inferior because the protruding amount of the support shaft g is large.

JP 2006-160236 A JP 2001-71393 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a rigid core holding structure capable of accurately and efficiently transferring a rigid core between apparatuses while simplifying and miniaturizing the holding structure.

In order to solve the above problem, the invention of claim 1 of the present application provides a rigid core having an annular core body provided with a molding surface on the outer surface for molding a lumen surface of a pneumatic tire. A holding structure of a rigid core that is held so as to be able to pass between the holding shaft portion of the device and the holding shaft portion of the second device,
The rigid core is
The core body comprising a plurality of core segments divided in the tire circumferential direction and movable inward in the radial direction;
A cylindrical core that is inserted into the center hole of the core body and prevents the core segments from moving radially inward;
A pair of side plates disposed on both sides of the core body in the axial direction, and holding the core body between the inner side surfaces to prevent movement of each core segment in the axial direction;
And on the outer surface of each side plate is provided with a support shaft portion protruding outward in the axial direction,
The support shaft portion and the holding shaft portion are detachable by connecting means having a ball lock mechanism.

According to a second aspect of the present invention, the connecting means includes a connecting hole portion concentrically recessed at an outer end portion of the support shaft portion and provided with a circumferential groove on an inner peripheral surface, and an outer end portion of the holding shaft portion. Containing a connecting cylinder portion projecting concentrically and inserted into the connecting hole portion, and ball locking means for locking between the connecting hole portion and the connecting cylinder portion,
The ball lock means includes
A rigid ball that is dispersedly arranged in the circumferential direction in the connecting cylinder part and is held in a plurality of through holes that penetrate inward and outward in the radial direction;
A piston piece housed in a cylinder chamber provided in the holding shaft portion, and movable inward and outward in the axial direction in the cylinder chamber by supplying and discharging compressed air to and from the cylinder chamber;
A plunger arranged in a central hole of the connecting cylinder portion and connected to the piston piece so as to be movable together with the piston piece;
The plunger pushes each rigid ball radially outward by moving to one side in the axial direction within the central hole of the connecting cylinder portion by the piston piece, and presses and locks each rigid ball to the circumferential groove. In addition, the piston piece moves to the other side in the axial center direction within the central hole of the connecting cylinder part to release the rigid ball from being pushed out in the radial direction, and between the connecting hole part and the connecting cylinder part. It is characterized by releasing the lock.

  According to a third aspect of the present invention, the core segment has a large width in the circumferential direction, and the split surfaces at both ends in the circumferential direction are inclined in such a direction that the circumferential width decreases toward the inside in the radial direction. The child segments and the first core segments are alternately arranged in the circumferential direction, and the circumferential width is small, and the circumferential width is increased inward in the radially inward direction on the divided surfaces at both circumferential ends. It is characterized by being configured to be movable inward in the radial direction by being composed of the second core segment inclined to the center.

  As described above, the rigid core of the present invention protrudes the support shaft part on both sides in the axial direction. Therefore, it is possible to connect the other support shaft portion to the holding shaft portion of another device while holding one support shaft portion, and to improve the work efficiency of delivering the rigid core. In addition, since the ball lock mechanism is employed as the connecting means, one-touch attachment / detachment is possible, and the connection accuracy and connection efficiency between the support shaft portion and the holding shaft portion during delivery can be further increased.

  Further, by adopting the ball lock mechanism, the structure of the connecting means can be simplified, and the protruding amount of the support shaft portion can be kept low. In particular, in the present invention, since the support shaft portions are protruded on both sides in the axial direction, it is important to reduce the protrusion amount of the support shaft portion in order to improve the handleability of the rigid core.

It is sectional drawing which shows one Example of the holding structure of the rigid core of this invention. It is a top view which shows a core main body with a core. It is a disassembled perspective view of a rigid core. It is an enlarged view which shows the engagement state of the 1st, 2nd dovetail part. It is sectional drawing explaining a connection means. It is explanatory drawing which shows the effect of the holding structure of a rigid core. (A) is sectional drawing which shows the formation method of the pneumatic tire which used the rigid core, (B) is a side view of the axial direction of a rigid core.

Hereinafter, embodiments of the present invention will be described in detail.
As shown in FIG. 1, the rigid core holding structure (hereinafter referred to as a holding structure) of the present embodiment includes a rigid core 1, a holding shaft portion 51 </ b> A of the first device 50 </ b> A, and a second device 50 </ b> B. A holding structure for holding the holding shaft portion 51B so as to be able to deliver the holding shaft portion 51B. The rigid core 1 is provided with support shaft portions 12 protruding outward in the axial direction, and each of the support shaft portions 12 and The holding shaft portions 51A and 51B are configured to be detachable by connecting means 24 having a ball lock mechanism.

  In this example, one of the first and second devices 50A, 50B is a tire forming device such as an inner liner attaching device, a carcass ply attaching device, a belt ply attaching device, a sidewall rubber attaching device, a tread rubber attaching device, or the like. And the other is a transfer device that receives the rigid core 1 from the selected tire forming device and then sequentially transfers the rigid core 1 to another tire forming device. Indicated. Thereby, a plurality of tire constituent members can be sequentially attached to the rigid core 1 to form a raw tire. The first and second devices 50A and 50B are not limited to this, and various devices such as other tire vulcanizing devices and inspection devices can be applied.

  The rigid core 1 is inserted into an annular core body 3 provided on the outer surface with a molding surface 2 for molding the lumen surface Ts of the pneumatic tire T, and a center hole 3H of the core body 3. A cylindrical core 5 and a pair of side plates 6F and 6R arranged on both sides in the axial direction of the core body 3 are provided. And the supporting shaft parts 12 and 12 which protrude to an axial direction outer side are provided in the outer surface of each side plate 6F and 6R.

  In this example, the core body 3 has a taper surface 7 inclined inward in the axial direction toward the inner side in the radial direction on the inner side in the radial direction of the main portion 3A having the molding surface 2. A concave portion 8 concentric with the core body 3 is formed inside the core body 3 while having a bulging portion 3B that bulges outward. In this example, a case where steam, which is a heat medium for vulcanization heating, is supplied into the recess 8 through a flow path (not shown) provided in the core 5 is shown. A heat source for vulcanization heating can be accommodated in the recess 8.

  As shown in FIGS. 2 and 3, the core body 3 is composed of a plurality of core segments 9 divided in the tire circumferential direction. The core segment 9 has divided surfaces 9S at both ends in the circumferential direction. The first core segments 9A inclined in the direction of decreasing the circumferential width toward the inside in the radial direction and the first core segments 9A are alternately arranged in the circumferential direction, and divided at both ends in the circumferential direction. The surface 9S is composed of a second core segment 9B that is inclined in the direction in which the circumferential width increases inward in the radial direction. As a result, the core segment 9 can move the second core segment 9B radially inward, and accordingly, the first core segment 9A can also be sequentially moved radially inward. Therefore, the core body 3 can be sequentially removed from the inner cavity TH of the tire T by moving one by one radially inward from the second core segment 9B.

  Next, the core 5 has a cylindrical shape and is inserted into the center hole 3H of the core body 3 to prevent the core segments 9 from moving inward in the radial direction. In this example, the end of one side in the axial direction of the core 5 is fixed to the inner side surface of the side plate 6F on the one side in the axial direction. In this example, the case where the side plate 6F and the core 5 are fixed using a bolt 10 (shown in FIG. 1) is shown. However, when the rigid core 1 is disassembled and taken out from the tire T, it is not necessary to disassemble the side plate 6F and the core 5 on the one side. It has no effect on it. Therefore, the side plate 6F and the core 5 can be fixed by, for example, welding.

  The side plate 6F on the one side includes a side plate body 11 having a disc-shaped substrate portion 11A and a flange portion 11B that is provided on the outer circumferential edge of the substrate plate 11A and contacts the tapered surface 7 of the core body 3. A support shaft portion 12 that protrudes outward in the axial direction is provided concentrically on the outer surface of the substrate portion 11A. The flange portion 11B has the same inclination as the tapered surface 7, thereby allowing the side plate 6F and the core body 3 to be aligned concentrically, and between the flange portion 11B and the core 5, the intermediate portion The bulging portion 3B of the child main body 3 can be sandwiched and held.

  In addition, in this example, the core 5 includes an inner screw portion 13 on the other side in the axial direction of the center hole 5H, and a dovetail groove 14 extending continuously in the axial direction on the outer peripheral surface of the core 5. Alternatively, the first ant joint portion 16 made of one of the ant tenons 15 is formed. Further, on the inner peripheral surface of each core segment 9, a second dovetail portion 17 comprising the other of the dovetail groove 14 or the dovetail tenon 15 extending in the axial direction and engaging with the first dovetail portion 16. Is formed. In this example, the case where the dovetail groove 14 is formed as the first dovetail joint 16 and the ant tenon 15 is formed as the second dovetail joint 17 is shown, but conversely the first dovetail joint 16 The ant tenon 15 may be formed, and the ant groove 14 may be formed as the second ant joint 17. As shown in FIG. 4, the dovetail groove 14 and the ant tenon 15 have a substantially trapezoidal cross section in which both side surfaces are inclined in the direction of increasing the width toward the groove bottom and tenon tip, The other is engaged with each other so as to be relatively movable only in the axial direction.

  Next, the side plate main body 20 </ b> R on the other side in the axial direction has a disk-shaped substrate portion 20 </ b> A and a flange portion 20 </ b> B that is provided on the outer circumferential edge and abuts against the tapered surface 7 of the core main body 3. And a support shaft portion 12 projecting outward in the axial direction is provided concentrically on the outer surface of the substrate portion 20A.

  Further, a boss portion 22 that can be screwed into an inner screw portion 13 provided in the center hole 5H of the core 5 is provided concentrically on the inner side surface of the substrate portion 20A. Therefore, the other side plate 6R can be detachably attached to the core 5 by the boss portion 22 and the inner screw portion 13. Further, at the time of mounting, the flange portion 20B aligns the side plate 6R and the core body 3 concentrically as well as the side plate 6F, and between the flange portion 20B and the core 5, the core body 3 The bulging portion 3B can be sandwiched and held.

  Thus, in the rigid core 1 of this example, since the first and second dovetail portions 16 and 17 are formed in the core 5 and each core segment 9, respectively, each core segment 9 is It can be sequentially arranged around the core while being guided by the first dovetail portion 16. In addition, since the first and second dovetail joint portions 16 and 17 are engaged with each other, positional displacement of the core segment 9 can be prevented and high-precision and stable assembly can be achieved.

  Further, since the boss portion 22 that can be screwed to the core 5 protrudes from the other side plate 6R, the core body 3 is held between the side plates 6F and 6R by the screwing of the boss portion 22. Thus, the movement of each core segment 9 in the axial direction can be prevented. Therefore, the engagement between the first and second dovetail joint portions 16 and 17, the movement of the core segment 9 in the radial direction by the core 5, and the sandwiching between the side plates 6F and 6R. By preventing movement of the core segment 9 in the axial direction, the assembled core segments 9 and 9 can be fixed, and the core body 3 can be maintained with high accuracy. In addition, in this example, the rigid core 1 is fixed by only one screwed connection between the side plate 6R and the core 5 without using bolts, so that the assembly work efficiency and the disassembly work efficiency can be greatly improved. And can greatly contribute to the automation of assembly and disassembly. The side plate 6R and the core 5 can be detachably connected using bolts.

  In this embodiment, the support shafts 12 and 12 on both sides and the holding shafts 51A and 51B of the first and second devices 50A and 50B are detachable by a connecting means 24 having a ball lock mechanism. It is configured. Hereinafter, the holding shaft portions 51A and 51B are collectively referred to as a holding shaft portion 51.

  As illustrated in FIG. 5, the connecting means 24 includes a connecting hole portion 26 that is concentrically recessed at the outer end portion of the support shaft portion 12 and provided with a circumferential groove 26 </ b> A on the inner peripheral surface. A connecting tube portion 27 that is concentrically protruded from the outer end portion of the holding shaft portion 51 and is inserted into the connecting hole portion 26, and ball lock means 28 that locks between the connecting hole portion 26 and the connecting tube portion 27. With

  The ball lock means 28 includes a rigid ball 30 that is dispersedly arranged in the circumferential direction in the connecting cylinder portion 27 and that is held in a plurality of through holes 29 penetrating inward and outward in the radial direction, and a cylinder chamber provided in the holding shaft portion 51. The piston piece 33 is accommodated in the cylinder chamber 31 and can be moved in and out in the axial direction in the cylinder chamber 31 by supply and discharge of compressed air to and from the cylinder chamber 31, and the central hole 27 </ b> H of the connecting cylinder portion 27. And a plunger 34 connected to the piston piece 33 so as to be movable together.

  The plunger 34 can move outward in the axial direction in the center hole 27H of the connecting cylinder portion 27 by the piston piece 33. As a result of this movement, the outer peripheral surface of the plunger 34 abuts on each of the rigid balls 30 and pushes it up radially outward, and the rigid balls 30 can be pressed against the circumferential groove 26A and locked. The plunger 34 can be moved axially inward in the center hole 27H of the connecting cylinder portion 27 by the piston piece 33, thereby releasing the push-up of the rigid ball 30 outward in the radial direction. The lock between the part 26 and the connecting cylinder part 27 is released. The outer peripheral surface of the plunger 34 has a cone surface that tapers outward in the axial direction.

  Further, the outer end surface of the support shaft portion 12 is formed with a locking portion 36 (shown in FIG. 3) formed of one of a key groove for rotation prevention or a key-like projection, and the outer end surface of the holding shaft portion 51. Is formed with the other of the keyway or the key-like protrusion, and an engaging portion (not shown) that engages with the locking portion 36 is formed.

  As described above, since the rigid core 1 of the present embodiment protrudes the support shaft portions 12 and 12 on both sides in the axial direction, as shown schematically in FIG. 6, one support shaft portion 12 is connected to one device 50A. While being connected to the holding shaft portion 51A of the first device 50A (for example, the first device 50A), the other support shaft portion 12 can be connected to the holding shaft portion 51B of the other device 50B (for example, the second device 50B), The delivery operation of the rigid core 1 can be performed efficiently. In addition, since the ball locking mechanism is employed for the connecting means 24, one-touch attachment / detachment is possible, and the connection accuracy and the connection efficiency between the support shaft portion 12 and the holding shaft portions 51A and 51B at the time of delivery are further increased. be able to. Furthermore, by adopting a ball lock mechanism, the structure of the connecting means 24 can be simplified, and the protruding amount of the support shaft portion 12 can be kept low, so that when the support shaft portion 12 protrudes on both sides in the axial direction. Also, the rigid core 1 can be kept compact.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

DESCRIPTION OF SYMBOLS 1 Rigid core 2 Molding surface 3 Core body 3H Center hole 5 Core 5H Center holes 6F, 6R Side plate 9 Core segment 9A First core segment 9B Second core segment 9S Split surface 12 Support shaft T Air Enter tire Ts Lumen surface

Claims (3)

A rigid core including an annular core body having a molding surface for molding a lumen surface of a pneumatic tire provided on an outer surface, a holding shaft portion of a first device, and a holding shaft portion of a second device A rigid core holding structure that can be passed between and
The rigid core is
The core body comprising a plurality of core segments divided in the tire circumferential direction and movable inward in the radial direction;
A cylindrical core that is inserted into the center hole of the core body and prevents the core segments from moving radially inward;
A pair of side plates disposed on both sides of the core body in the axial direction, and holding the core body between the inner side surfaces to prevent movement of each core segment in the axial direction;
And on the outer surface of each side plate is provided with a support shaft portion protruding outward in the axial direction,
A rigid core holding structure, wherein the support shaft portion and the holding shaft portion are detachable by a connecting means having a ball lock mechanism. The connecting means is a connecting hole portion concentrically recessed at an outer end portion of the support shaft portion and provided with a circumferential groove on an inner peripheral surface, and is provided concentrically and protruded at an outer end portion of the holding shaft portion. A connecting cylinder part to be inserted into the hole, and ball locking means for locking between the connecting hole part and the connecting cylinder part;
The ball lock means includes
A rigid ball that is dispersedly arranged in the circumferential direction in the connecting cylinder part and is held in a plurality of through holes that penetrate inward and outward in the radial direction;
A piston piece housed in a cylinder chamber provided in the holding shaft portion, and movable inward and outward in the axial direction in the cylinder chamber by supplying and discharging compressed air to and from the cylinder chamber;
A plunger arranged in a central hole of the connecting cylinder portion and connected to the piston piece so as to be movable together with the piston piece;
The plunger pushes each rigid ball radially outward by moving to one side in the axial direction within the central hole of the connecting cylinder portion by the piston piece, and presses and locks each rigid ball to the circumferential groove. In addition, the piston piece moves to the other side in the axial center direction within the central hole of the connecting cylinder part to release the rigid ball from being pushed out in the radial direction, and between the connecting hole part and the connecting cylinder part. 2. The rigid core holding structure according to claim 1, wherein the lock is released.   The core segment has a first core segment having a large circumferential width and inclined split surfaces at both ends in the circumferential direction in a direction in which the circumferential width decreases inward in the radial direction; The core segments are alternately arranged in the circumferential direction, the circumferential width is small, and the dividing surfaces at both ends in the circumferential direction are inclined in the direction of increasing the circumferential width inward in the radial direction. 2. The rigid core holding structure according to claim 1, wherein the rigid core holding structure is configured to be movable inward in the radial direction by being configured with a child segment.

Images