Patent Publication Number: US-2023150218-A1

Title: Tire vulcanizing apparatus

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to a tire vulcanizing apparatus. 
     Background Art 
     Japanese Laid-Open Patent Publication No. 2020-168794 discloses a tire vulcanizing apparatus including a mold in which a split position between a side mold and a tread mold is shifted inwardly in the tire radial direction. In this type of tire vulcanizing apparatus, when the tread mold is opened outwardly in the tire radial direction, the tread mold is likely to be caught by a side block of a tire, and removal of the tire from the mold tends to become impossible. Therefore, the tire vulcanizing apparatus includes a first lifting and lowering device for lowering an upper side mold in order to press-contract the width of the tire in advance. The first lifting and lowering device is disposed above the mold and is implemented by a cylinder including a rod. 
     In the tire vulcanizing apparatus described above, the rod of the first lifting and lowering device and the upper side mold are mechanically connected to each other. Therefore, an operation of connecting the mold to the rod of the first lifting and lowering device needs to be performed each time the mold is set and detached. This operation needs to be performed in a limited and narrow operation space, and requires much labor. 
     The present disclosure has been made in view of the aforementioned circumstances, and a main object of the present disclosure is to provide a tire vulcanizing apparatus capable of lowering an upper side mold without mechanical combination between a mold and a lowering force application device. 
     SUMMARY 
     The present disclosure is directed to a tire vulcanizing apparatus including: a mold in which a green tire is placed horizontally and vulcanized, the mold including a tread mold, an upper side mold, and a lower side mold; a lowering force application device disposed above the mold, the lowering force application device including a rod extending downward; and an attachment fixed to an upper portion of the mold without mechanical combination with the rod. The attachment includes a body, and an upward-downward movable portion that is movable relative to the body in an up-down direction and fixed to the upper side mold. The upward-downward movable portion lowers, upon receiving a lowering force from the rod, the upper side mold relative to the tread mold. 
     The tire vulcanizing apparatus of the present disclosure has the above-described structure, and thus can lower the upper side mold without mechanical combination between the mold and the lowering force application device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a side view conceptually showing a tire vulcanizing apparatus according to one embodiment of the present disclosure; 
         FIG.  2    is a partially enlarged view of  FIG.  1   ; 
         FIG.  3    is an enlarged view of an attachment in  FIG.  1   ; 
         FIG.  4 A  is a cross-sectional view conceptually showing a state where a lowering force is applied by a lowering force application device; 
         FIG.  4 B  is a cross-sectional view conceptually showing a state where the lowering force has been released; 
         FIG.  5 A  is a cross-sectional view conceptually showing a step of assembling the tire vulcanizing apparatus; 
         FIG.  5 B  is a cross-sectional view conceptually showing the step of assembling the tire vulcanizing apparatus; and 
         FIG.  6    is a cross-sectional view conceptually showing the step of assembling the tire vulcanizing apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     One embodiment of the present disclosure will be described below with reference to the drawings. 
       FIG.  1    is a cross-sectional view conceptually showing a tire vulcanizing apparatus (hereinafter, may be referred to as “apparatus”)  1  according to one embodiment of the present disclosure. The apparatus  1  of the present disclosure vulcanizes a green tire T (shown in  FIG.  2   ) to produce a pneumatic tire (not shown). The apparatus  1  is suitable for, for example, producing pneumatic tires for four-wheel-drive vehicles such as an SUV. However, the apparatus  1  is also used for producing pneumatic tires for passenger cars and motorcycles and heavy-duty pneumatic tires. 
     As shown in  FIG.  1   , the apparatus  1  of the present embodiment includes a mold  2  in which the green tire T is placed horizontally and vulcanized, an apparatus body  3  for supporting the mold  2  such that the mold  2  can be opened/closed, and an attachment  4  fixed to the upper portion of the mold  2 . In the present embodiment, the tire axial direction of the green tire T in the mold  2  is oriented in the vertical (up-down) direction, and the tire circumferential direction and the tire radial direction of the green tire T are oriented in the horizontal direction. In the description herein, the circumferential direction, the axial direction, and the radial direction of the green tire T correspond to the tire circumferential direction, the tire axial direction, and the tire radial direction, respectively. 
       FIG.  2    is an enlarged view of  FIG.  1   . The green tire T is shown in  FIG.  2   . As shown in  FIG.  1    and  FIG.  2   , the mold  2  of the present embodiment includes a tread mold  6 , an upper side mold  7 U, a lower side mold  7 L, an upper plate  8 , a lower plate  10 , and an actuator  11 . In the present embodiment, the tread mold  6  has a known structure including a plurality of segments  6   a  that are segmented in the tire circumferential direction, and has, for example, a molding surface a 1  that allows molding of the outer surface located outward of the maximum width position (now shown) of the pneumatic tire in the tire radial direction. In the present embodiment, each segment  6   a  is held by a sector  9  having a known structure so as to be replaceable. The upper plate  8  of the present embodiment has a known structure, and supports the tread mold  6 . The lower plate  10  has, for example, a known structure, and allows the lower side mold  7 L to be placed thereon. The actuator  11  of the present embodiment has a known structure, and supports the sector  9  so as to increase and reduce the diameter of the sector  9  in the tire radial direction. 
     In the present embodiment, each of the upper side mold  7 U and the lower side mold  7 L has a known structure, and has a molding surface a 2  that allows molding of the outer surface, of the pneumatic tire, located inward of the tire maximum width position (not shown) in the tire radial direction. The upper side mold  7 U includes, for example, a first portion  12   a  that includes the molding surface a 2  and annularly extends, and a second portion  12   b  that is connected to the inner circumferential side of the first portion  12   a  and that has a disk-like shape having a thickness less than the first portion  12   a.    
     As shown in  FIG.  1   , the apparatus body  3  includes a lower body  15  disposed below the mold  2  and an upper body  16  disposed above the mold  2 . 
     The lower body  15  of the present embodiment has a known structure that includes a lower base  17  for fixing the lower plate  10 , a center mechanism  18  attached to the lower base  17 , and a first lifting and lowering device  19  capable of relatively moving the lower side mold  7 L relative to the lower plate  10  in the up-down direction. The center mechanism  18  of the present embodiment includes a vulcanization bladder (not shown). The center mechanism  18  includes an upper grip ring  20   a  (shown in  FIG.  2   ) for holding the upper end of the vulcanization bladder, a lower grip ring  20   b  for holding the lower end of the vulcanization bladder, and a second lifting and lowering device  21  for relatively moving the upper grip ring  20   a  relative to the lower grip ring  20   b  in the up-down direction. 
     In the present embodiment, the first lifting and lowering device  19  and the second lifting and lowering device  21  are implemented by cylinder mechanisms having known structures and having rods  19   a  and  21   a,  respectively, extending in the up-down direction. To the rod  19   a  of the first lifting and lowering device  19 , a first support cylinder  22  having a cylindrical shape is fixed via a plate-shaped connecting portion K. The first support cylinder  22  supports the lower side mold  7 L via a holder  23 . The rod  21   a  of the second lifting and lowering device  21  extends in the center hole of the first support cylinder  22 , and the upper grip ring  20   a  is fixed to the rod  21   a.    
     The upper body  16  of the present embodiment includes, for example, a lowering force application device  25 , an upper lifting and lowering device  26 , and an upper base  27 . The lowering force application device  25  of the present embodiment has, for example, a function of lowering the upper side mold  7 U relative to the tread mold  6 . 
     The upper base  27  includes a top plate  28   a  for supporting the upper lifting and lowering device  26 , a lifting and lowering plate  28   b  disposed below the top plate  28   a,  and a support member  28   c  that connects the lifting and lowering plate  28   b  and the top plate  28   a  to each other and extends in the up-down direction. 
     The lifting and lowering plate  28   b  supports the actuator  11 . The lifting and lowering plate  28   b  can be moved relative to the upper plate  8  in the up-down direction by a lifting and lowering device (not shown) that is implemented by, for example, a cylinder mechanism and that has a known structure. 
     The upper lifting and lowering device  26  has, for example, a function of moving the upper plate  8  in the up-down direction. The upper lifting and lowering device  26  of the present embodiment is implemented by a cylinder mechanism having a known structure and having a rod  26   a.  A second support cylinder  32  having a cylindrical shape is fixed to the lower end of the rod  26   a  of the upper lifting and lowering device  26  via a connecting portion  31 . In the present embodiment, a flange portion  32   a  protruding toward the outer circumferential side is formed at the lower end of the second support cylinder  32 . 
     The lowering force application device  25  includes a rod  25   a  extending downward. The lowering force application device  25  is, for example, implemented by a cylinder mechanism having a known structure and having the rod  25   a.  Thus, the rod  25   a  of the lowering force application device  25  applies a lowering force acting in the downward direction. In the present embodiment, the lowering force application device  25  is supported by the connecting portion  31 . The rod  25   a  of the lowering force application device  25  extends through the center hole of the second support cylinder  32  in the up-down direction. The attachment  4  is disposed below the rod  25   a.  The rod  25   a  of the present embodiment extends downward of the lower end of the second support cylinder  32 . 
       FIG.  3    is an enlarged view of the attachment  4  in  FIG.  1   . As shown in  FIG.  3   , the attachment  4  includes a body  35  and an upward-downward movable portion  36  that is movable relative to the body  35  in the up-down direction. The body  35  of the present embodiment includes an opening  35   a  penetrating in the up-down direction, a first flange portion  35   b  disposed at the upper end of the body  35  so as to protrude toward the outer circumferential side, and a second flange portion  35   c  disposed at the lower end of the body  35  so as to protrude toward the outer circumferential side. The upward-downward movable portion  36  of the present embodiment includes an axial portion  37  extending in the up-down direction, and a plate-shaped connecting portion  38  connected to the lower end of the axial portion  37 . 
     The body  35  is, for example, fixed by bolts (bolt-fixing B 1 ) to the mold  2  from the upper side of the mold  2 . In the present embodiment, the second flange portion  35   c  and the upper plate  8  are fixed by bolts (bolt-fixing B 1 ) to each other. The first flange portion  35   b  is in contact with the flange portion  32   a  of the second support cylinder  32 . The flange portion  32   a  of the second support cylinder  32  and the first flange portion  35   b  are, for example, preferably fixed by a fixing tool (not shown) having a known structure so as to be attachable/detachable. 
     The upward-downward movable portion  36  is, for example, fixed by bolts (bolt-fixing B 2 ) to the upper side mold  7 U from thereabove. In the present embodiment, the connecting portion  38  and the second portion  12   b  of the upper side mold  7 U are fixed by bolts that are inserted from through holes  40  disposed in the second flange portion  35   c.  In the present embodiment, the rod  25   a  is inserted in the opening  35   a  such that an upper end  37   a  of the axial portion  37  and a lower end  25   e  of the rod  25   a  of the lowering force application device  25  are in contact with each other. Thus, the rod  25   a  and the attachment  4  (the axial portion  37  of the upward-downward movable portion  36 ) are not mechanically combined with each other. In the present embodiment, the upper end  37   a  of the axial portion  37  is disposed downward of the upper end  35   e  of the opening  35   a.    
     Thus, as shown in  FIG.  4 A , the upward-downward movable portion  36  can lower, upon receiving a lowering force F from the rod  25   a,  the upper side mold  7 U fixed to the connecting portion  38  relative to the tread mold  6 . Meanwhile, when downward extension (lowering force F) of the rod  25   a  is released and the rod  25   a  is moved upward, the rod  25   a  and the axial portion  37  of the upward-downward movable portion  36  enter a state of being (instantaneously) separated from each other (shown in  FIG.  4 B ). By extension and contraction of the rod  26   a  of the upper lifting and lowering device  26 , the upper plate  8  and the tread mold  6  can be integrally moved in the up-down direction via the connecting portion  31 , the second support cylinder  32 , and the body  35  (not shown). 
     The attachment  4  further includes a coil spring  41 . The coil spring  41  is movable together with the axial portion  37  in the opening  35   a,  and is held in a state of being prevented from being removed from the opening  35   a.  Thus, upon receiving the lowering force F from the rod  25   a,  the axial portion  37  is lowered, whereby a compressive force acts on the coil spring  41  (shown in  FIG.  4 A ). When the lowering force F is released and the state is as shown in  FIG.  4 B , the compressive force of the coil spring  41  can urge the upward-downward movable portion  36  upward relative to the body  35 . Thus, by the coil spring  41 , the upward-downward movable portion  36  can be moved upward together with the upper side mold  7 U so as to come into contact with the rod  25   a.  The “state where the coil spring  41  is prevented from being removed” is achieved by a known structure as shown in the drawings, and the description thereof is omitted. 
     Thus, in the apparatus  1  of the present embodiment, the upward-downward movable portion  36  of the attachment  4  lowers, upon receiving the lowering force F of the lowering force application device  25 , the upper side mold  7 U relative to the tread mold  6 . The mold  2  and the lowering force application device  25  are mounted via the attachment  4  that is not mechanically combined with the rod  25   a  of the lowering force application device  25 . Therefore, in the apparatus  1 , the upper side mold  7 U can be lowered without mechanical combination between the mold  2  and the lowering force application device  25 . 
     Furthermore, the apparatus  1  of the present embodiment preferably includes a controller (not shown) for operating each of the lifting and lowering devices  19 ,  21 , and  26 , and the lowering force application device  25 . The controller is preferably implemented by, for example, a computer or the like, and stores, for example, an operation procedure and an operation amount for each of the lifting and lowering devices  19 ,  21 , and  26 , and the lowering force application device  25 . 
     Next, an assembling step of assembling the apparatus  1  having such a structure will be described.  FIG.  5    and  FIG.  6    are schematic diagrams illustrating a flow of the assembling step. As shown in  FIG.  5 A , the mold  2  and the attachment  4  are firstly prepared. In the present embodiment, the mold  2  is mounted to the lower body  15 . The mold  2  includes, for example, the tread mold  6 , the upper side mold  7 U, the lower side mold  7 L, the actuator  11 , the upper plate  8 , and the lower plate  10 , which are in a closed state (the same state as a state during vulcanization). The attachment  4  is disposed above the mold  2 . 
     Subsequently, as shown in  FIG.  5 B , the attachment  4  is fixed to the mold  2 . The body  35  of the attachment  4  is fixed by bolts (bolt-fixing B 1 ) to the upper plate  8 . By using the through holes  40  of the second flange portion  35   c,  the upward-downward movable portion  36  of the attachment  4  is fixed by bolts (bolt-fixing B 2 ) to the upper side mold  7 U. Thus, in the apparatus  1  of the present embodiment, the attachment  4  is easily attached by using a wide space above the mold  2 . 
     Subsequently, as shown in  FIG.  6   , the upper body  16  is attached on the mold  2 . In the present embodiment, the lifting and lowering plate  28   b  of the upper body  16  is fixed to the actuator  11 , and the rod  25   a  of the lowering force application device  25  is inserted in the opening  35   a  so as to come into contact with the upper end  37   a  of the axial portion  37  of the upward-downward movable portion  36 . Thus, the upper body  16  and the mold  2  are also attached to each other by using a wide space above the mold  2 , whereby labor can be reduced. 
     Although the particularly preferred embodiment of the present disclosure has been described above in detail, the present disclosure is not limited to the illustrated embodiment, and various modifications can be made to implement the technique of the present disclosure. 
     [Appendix] 
     The present disclosure includes the following aspects. 
     [Disclosure 1] 
     A tire vulcanizing apparatus including: 
     a mold in which a green tire is placed horizontally and vulcanized, the mold including a tread mold, an upper side mold, and a lower side mold; 
     a lowering force application device disposed above the mold, the lowering force application device including a rod extending downward; and 
     an attachment fixed to an upper portion of the mold without mechanical combination with the rod, in which 
     the attachment includes a body, and an upward-downward movable portion that is movable relative to the body in an up-down direction and fixed to the upper side mold, and 
     the upward-downward movable portion lowers, upon receiving a lowering force from the rod, the upper side mold relative to the tread mold. 
     [Disclosure 2] 
     The tire vulcanizing apparatus according to disclosure 1, in which the body of the attachment is fixed by a bolt to the mold from above the mold. 
     [Disclosure 3] 
     The tire vulcanizing apparatus according to disclosure 1 or 2, in which the upward-downward movable portion is fixed by a bolt to the upper side mold from thereabove. 
     [Disclosure 4] 
     The tire vulcanizing apparatus according to disclosure 3, in which the upward-downward movable portion is urged upward relative to the body so as to move the upper side mold to an upper position due to the upward-downward movable portion being separated from the rod. 
     [Disclosure 5] 
     The tire vulcanizing apparatus according to disclosure 4, in which the attachment includes a coil spring for urging the upward-downward movable portion upward relative to the body. 
     [Disclosure 6] 
     The tire vulcanizing apparatus according to disclosure 5, in which 
     the body has an opening penetrating in an up-down direction, and 
     the upward-downward movable portion and the coil spring are movable in the opening and are held in a state of being prevented from being removed from the opening.