Abstract:
There is provided a tire vulcanizing system which can easily be arranged in an existing tire factory. The present invention provides a tire vulcanizing system having a vulcanizing station  100  for mounting a plurality of sets of tire mold assemblies M on a flat surface of a predetermined height and a tire mold opening/closing station  200  formed along the vulcanizing station  100,  in which a tire mold opening/closing device  210,  which takes out the tire mold assembly M from the vulcanizing station  100,  and opens and closes the tire mold assembly M, is provided at the tire mold opening/closing station  200,  and the tire mold opening/closing device  210  is provided with an upper movable plate  206  capable of elevating an upper mold Ma of the tire mold assembly M by connecting with the upper mold Ma, a horizontal transfer device  215  for transferring the tire mold assembly M on the same level as the height of the flat surface, and a lower fixed plate  211  capable of fixing a lower mold Mb of the tire mold assembly M.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a tire vulcanizing system.  
           [0003]    2. Description of the Related Art  
           [0004]    In a conventional fully automatic tire vulcanizing press, the work time for loading and shaping a green tire and for unloading a vulcanized tire is far shorter than the time over which vulcanization is performed by introducing a heating/pressurizing medium in a tire in a state in which a tire mold assembly is closed. Therefore, a tire mold opening/closing device for opening/closing the tire mold assembly to loading/unloading a tire after the completion of vulcanization and a tire loading/unloading device are low in operation efficiency.  
           [0005]    To solve this problem, the applicant of this invention has already proposed a tire vulcanizing system disclosed in Japanese Patent Provisional Publication No. 7-80846 (No. 80846/1995). This tire vulcanizing system comprises vulcanizing stations a 1  and a 2 , mold opening/closing stations b 1  and b 2 , tire mold transporters c 1  and c 2 , rails d for the tire mold transporters, mold beds e 1  to e 3 , tire mold opening/closing devices f 1  and f 2 , unloaders g 1  and g 2 , loaders h 1  and h 2 , conveyors i 1  and i 2  for conveying vulcanized tires, racks j 1  and j 2  for green tires, and a mold changing table (a mold changing table for changing a tread mold, side wall mold, etc. in a tire mold assembly to accommodate a change of specification of a tire to be vulcanized and for changing a bladder, which is an expendable) k.  
           [0006]    The following is a description of a tire vulcanizing process using a tire vulcanizing system having the above-described configuration.  
           [0007]    First, a tire mold assembly M for which vulcanization has been finished is received by the tire mold transporter c 1  from the vulcanizing station a 1  (or a 2 ) at which a plurality of tire mold assemblies M being vulcanized are arranged, and is transported to the mold opening/closing station b 1 . Then, after the tire mold assembly M having transported to the mold opening/closing station b 1  is connected to the tire mold opening/closing device f 1 , the tire mold assembly M is opened by the tire mold opening/closing device f 1 , and a vulcanized tire is unloaded by the unloader g 1  attached to the tire mold opening/closing device f 1 . Next, a green tire is loaded, by using a loader h 1  attached to the tire mold opening/closing device f 1 , into the tire mold assembly M from which the vulcanized tire has been unloaded. Subsequently, after the loaded tire is shaped during a tire mold closing step and the tire mold assembly M is closed, a heating/pressurizing medium is introduced and sealed in the tire, by which a tire vulcanizing step is started. Then, the tire mold assembly M in which vulcanization has been started is disconnected from the tire mold opening/closing device f 1 , placed on the tire mold transporter c 1  again and transported, and returned to the vulcanizing station a 1 .  
           [0008]    When the above-described tire vulcanizing system is applied to a tire production facility whose vulcanization time is as short as, for example, 8 to 10 minutes, the following requirements are encountered.  
           [0009]    (1) The time over which the mold transporter receives a tire mold assembly at the vulcanizing station, the work at the mold opening/closing station is finished, and again, the closed tire mold assembly is transported and returned to the vulcanizing station must be made as short as possible. This is because the number of tire mold assemblies constituting the tire vulcanizing system cannot be increased from the economical viewpoint.  
           [0010]    (2) From the viewpoint of operation control in which a tire mold assembly having been used out during the operation is carried out, or a new tire mold assembly is put in during system operation in place of the carried-out tire mold assembly, it is preferable that the transportation time for each of the tire mold assemblies arranged in several numbers be made equal. Specifically, it is preferable that the transportation time for a tire mold assembly close to the mold opening/closing station be approximately equal to that for a tire mold assembly distant from the mold opening/closing station.  
           [0011]    (3) After the mold is closed at the mold opening/closing station, the heating/pressurizing medium introduced in the tire is temporarily sealed in the tire mold assembly during the transportation, and the heating/pressurizing medium is supplied again after the tire mold assembly arrives at the vulcanizing station. Here, considering the quality control of tire, the time of temporary sealing should preferably short.  
           [0012]    (4) When tires are continuously produced by using the tire vulcanizing system, green tires must be supplied continuously. For this purpose, it is necessary to store the most possible green tires in the vicinity of the loader disposed at the mold opening/closing station, and to supply new green tires successively.  
           [0013]    Therefore, it has been desired to provide a tire vulcanizing system having the following features: (1) The time taken for the tire mold assembly to be returned to the vulcanizing station can be shortened, and the transportation time for a tire mold assembly close to the mold opening/closing station and that for a tire mold assembly distant from the mold opening/closing station can be made approximately equal to each other. (2) The time for the heating/pressurizing medium to be sealed temporarily in the tire mold assembly can be shortened. (3) The most possible green tires can be stored in the vicinity of the loader disposed at the mold opening/closing station, and new green tires can be supplied successively, by which the installation area can be reduced significantly.  
           [0014]    To solve the above problem, the applicant of this invention has proposed a tire vulcanizing system disclosed in Japanese Patent Provisional Publication No. 8-164528 (No. 164528/1996). The operation of this tire vulcanization system is as described below. As shown in FIG. 5, first, at least two tire mold assemblies m (m 1 , m 4 , m 7 ) are stacked on a storage rack at a vulcanizing station  800 , and a mold opening/closing device  910  at a mold opening/closing station  900  is moved along the storage rack at the vulcanizing station  800 . Next, the tire mold assembly m is removed from the vulcanizing station  800 , and after the opening/closing of the tire mold assembly m, the unloading of a vulcanized tire t, and the loading of a green tire gt are performed, the tire mold assembly m is returned to the vulcanizing station  800 .  
           [0015]    However, in this tire vulcanizing system, since the vulcanizing station  800  is tall, a supply apparatus for green tires gt and a delivery apparatus for vulcanized tires t cannot be disposed over the vulcanizing station  800 , and these apparatuses must be disposed concentratedly on the opposite side of the vulcanizing station  800  at which the tire mold assemblies are stacked.  
         SUMMARY OF THE INVENTION  
         [0016]    Accordingly, an object of the present invention is to provide a tire vulcanizing system which can easily be arranged in an existing tire factory by arranging vulcanizing stations, the height of which is decreased, on a plane on the opposite sides of a movable tire mold opening/closing device, and by making spaces over the vulcanizing stations on both sides capable of being used for a green tire supply apparatus and a vulcanized tire delivery apparatus.  
           [0017]    To achieve the above object, the tire vulcanizing system in accordance with one mode of the present invention has a vulcanizing station for mounting a plurality of sets of tire mold assemblies in parallel on a flat surface of a predetermined height and a tire mold opening/closing station formed along the vulcanizing station, and is characterized in that a tire mold opening/closing device, which is movable along the vulcanizing station, takes out the tire mold assembly from the vulcanizing station, and opens and closes the tire mold assembly, is provided at the tire mold opening/closing station, and the tire mold opening/closing device is provided with an upper movable plate capable of elevating an upper mold of the tire mold assembly by connecting with the upper mold, a horizontal transfer device for transferring the tire mold assembly on the same level as the height of the flat surface, and a lower fixed plate capable of fixing a lower mold of the tire mold assembly.  
           [0018]    Also, the tire vulcanizing system in accordance with another mode of the present invention further has an unloader, which is movable integrally with the tire mold opening/closing device, for unloading a vulcanized tire, and a loader for loading a green tire.  
           [0019]    The above-described tire vulcanizing system has the vulcanizing stations and the tire mold opening/closing station, and the tire mold opening/closing station is provided with the tire mold opening/closing device. The tire mold opening/closing device, which moves along the vulcanizing station, takes out the tire mold assembly stored at the vulcanizing station, unloads the vulcanized tire in the tire mold assembly, loads a green tire in place of the vulcanized tire, and then returns the tire mold assembly to the vulcanizing station. Thereby, the time taken for the tire mold assembly to be returned to the vulcanizing station can be shortened, so that the quality control of tire can be carried out easily.  
           [0020]    For the tire vulcanizing system in accordance with the present invention, as described above, the vulcanizing stations are arranged on a plane, and the tire mold opening/closing device is moved along the vulcanizing station to take out the tire mold assembly from the vulcanizing station, to perform the opening/closing of the tire mold assembly, the unloading of the vulcanized tire, and the loading of a green tire, and then to return the tire mold assembly to the vulcanizing station. Therefore, the time taken for the tire mold assembly to be returned to the vulcanizing station can be shortened, and the transportation time for a tire mold assembly close to the tire mold opening/closing device can be made approximately equal to that for a tire mold assembly distant from the tire mold opening/closing device. Also, the time over which the heating/pressurizing medium is temporarily sealed in the tire mold assembly can be shortened, so that the quality control of tire can be carried out easily. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 is a plan view of a tire vulcanizing system in accordance with the present invention;  
         [0022]    [0022]FIG. 2 is a side view taken in the direction of the arrows along the line A-A of FIG. 1;  
         [0023]    [0023]FIG. 3 is a front view taken in the direction of the arrows along the line B-B of FIG. 2;  
         [0024]    [0024]FIG. 4 is a front view of a tire vulcanizing system including a mold change station; and  
         [0025]    [0025]FIG. 5 is a plan view of a conventional tire vulcanizing system. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0026]    The tire vulcanizing system in accordance with the present invention has two rows of vulcanizing stations on which tire mold assemblies are arranged and a tire mold opening/closing device which moves along the rack of vulcanizing station to take out a tire mold assembly from the vulcanizing station and to perform the opening/closing of the tire mold assembly, the unloading of a vulcanized tire, and the loading of a green tire. This tire vulcanizing system will be explained in detail with reference to FIGS.  1  to  4 .  
         [0027]    A vulcanizing station  100  comprises a plurality of sets of tire mold assemblies M (M 1  to M 6 ), a rack  101  for the vulcanizing station  100  for storing these tire mold assemblies M 1  to M 6 , guide roller groups  102  disposed on the rack  101 , and an internal pressure supply device (a device for supplying a heating/pressurizing medium into a tire) and an external pressure supply device (a device for supplying a heating/pressurizing medium to the outer peripheral portion of the tire mold) provided at appropriate places of the rack  101 , though not shown in the figures. For the tire mold assemblies M, in FIG. 1, the mold assemblies in the north row (upper stage) are denoted by M 1 , M 3 , and M 5 , and the tire mold assemblies M 2 , M 4 , and M 6  in the south row (lower stage) on the side opposite to the north row are not shown.  
         [0028]    The guide roller group  102  is on the same level, and also on the same level as a guide roller group  214  on a lower fixed plate  211 . Also, the configuration is such that when the tire mold assemblies M lie on the rack  101 , the centers of tire mold assemblies substantially agree with each other.  
         [0029]    In front (on the right side in FIG. 1) of the vulcanizing station  100 , a mold opening/closing station  200  is arranged. This mold opening/closing station  200  has horizontal straight rails  202  laid on a base  201  and a tire mold opening/closing device  210  sliding on the horizontal straight rails  202 . The tire mold opening/closing device  210  comprises, as shown in FIGS. 2 and 3, a frame  203 , vertical straight rails  204  provided on pillar portions  203   b  of the frame  203 , a guide bracket  205  sliding on the vertical straight rails  204 , an upper movable plate  206  assembled to the guide bracket  205 , cylinders  207  one end of which is assembled to the upper movable plate  206  and the other end of which is assembled to a transverse beam  203   a  of the frame  203 , a cylinder  208  for a split mold operating device disposed in the center of the upper movable plate  206 , an upper mold connecting device  209  disposed at an appropriate place at the outer peripheral portion of the upper movable plate  206 , a bladder operating mechanism  213  provided hangingly in the center of the lower fixed plate  211  on a lower transverse beam  203   c  of the frame  203 , the guide roller group  214  laid on the top surface of the lower fixed plate  211 , a stopper  203   d  provided on the top surface of the lower transverse beam  203   c  of the frame  203 , and a lower mold fixing device (not shown).  
         [0030]    On the lower fixed plate  211 , a horizontal transfer device  215  is provided to drive the guide roller group  214 . The tire mold assembly M is moved horizontally by using this horizontal transfer device  215 .  
         [0031]    As shown in FIG. 1, the pillar portion  203   b  of the frame  203  is provided with a loader  300  for a green tire GT on the face of row of even number of the north-side vulcanizing station. This loader  300  comprises a vertical straight rail (not shown) provided on the pillar portion  203   b  of the frame  203 , a bracket (not shown) sliding on the vertical straight rail, an arm  303  installed swingably to the bracket, a holder  304  having claws  304   a  provided so as to be capable of being expanded and contracted, and a cylinder (not shown) one end of which is fixed to the bracket and the other end of which is fixed to the frame  203 .  
         [0032]    On the opposite side (south side face) of the pillar portion  203   b  of the frame  203 , an unloader  400  is installed to unload a vulcanized tire T. This unloader  400  has almost the same configuration as that of the loader  300 , consisting of a holder  404  having holding claws  404   a,  an arm  403  for swinging the holder  404 , and other elements.  
         [0033]    As the tire mold assembly M, a tire mold assembly disclosed in Japanese Patent Provisional Publication No. 8-47928 (No. 47928/1996) is used. Specifically, there is used the tire mold assembly M in which a mold opening force is counterbalanced in the mold by the pressure of a high-temperature, high-pressure heating/pressurizing medium introduced in the tire during the vulcanization of tire, by which the necessity of clamping the mold from the outside to prevent the mold from opening is eliminated.  
         [0034]    The tire mold assemblies M shown in FIGS.  2  to  4  are of the above-described type, and a tire mold assembly M 1  (M 1   a,  M 1   b ) is in a state of being opened by the operation of the mold opening/closing station  200 . An upper mold M 1   a  is supported by the upper movable plate  206 , and a lower mold M 1   b  is supported by the lower fixed plate  211 . A bladder BL assembled to the lower mold M 1   b  is extended upward by the bladder operating mechanism  213  provided on the lower fixed plate  211 .  
         [0035]    On the south side of the mold opening/closing station  200 , that is, on the side of the unloader  400 , a tire delivery conveyor  500  is provided, and on the north side thereof, a green tire supply apparatus  600  is provided. These two apparatuses each are disposed on the upper floor over the vulcanizing station  100 . Of the floors F 2  for installing the delivery conveyor  500  and the green tire supply apparatus  600 , at the lower position on the side of the holder  304  of the loader  300 , green tire support beds  601 ,  602  and  603  are provided. These green tire support beds  601 ,  602  and  603  are provided at positions which are convenient when the frame  203  moves and performs work at its stop position.  
         [0036]    Of these green tire support beds, the bed  601  is used for a green tire for the tire mold assembly M 1 , the bed  602  is used for a green tire for the tire mold assembly M 2 , and the bed  603  is used for preparing a green tire for M 1  or M 2  to be used next. The green tire support beds turn between positions I, II and III. Specifically, when the tire mold opening/closing device  210  stops in front of the tire mold assemblies M 1  and M 2 , the green tire support beds are turned appropriately and stop so that the needed green tire comes just under the holder  304  of the loader  300 . At the aforementioned position I, a publicly known aerial carrier moving over this position unloads a green tire having carried from a publicly known automatic warehouse etc.  
         [0037]    A floor F 1  can be provided at the row end of the vulcanizing station  100  under the aforementioned floor F 2  (see FIG. 4), and the floor F 1  slidably accomodates a tire mold assembly M to be changed. If a tire mold assembly M is changed after the tire T is removed from the inside of the tire mold assembly M by the operation of the tire mold opening/closing device  210 , the tire mold assembly M is closed without the supply of a green tire GT by the tire mold opening/closing device  210 , and then is discharged onto the floor F 1  by using the horizontal transfer device  215  on the lower fixed plate  211 . The discharged tire mold assembly M is carried to a position of the tire mold assembly M indicated by the alternate long and short dash line in FIG. 4, and then the tire mold assembly M is taken away by publicly known means. After a new tire mold assembly M is assembled, it is put at an empty portion of the vulcanizing station  100  by reversing the above procedure. Subsequently, after predetermined operations such as preheating are finished, the new tire mold assembly is sent to the tire mold opening/closing device  210  at an appropriate time, being mounted with a green tire GT, and enters the vulcanizing step.  
         [0038]    The following is a description of the operation of the tire vulcanizing system shown in FIGS.  1  to  4 . Specifically, the operation of the tire mold assembly M 1  (M 1   a,  M 1   b ) stored at the vulcanizing station  100  is described.  
         [0039]    (1) When the completion of tire vulcanization in the tire mold assembly M 1  is close at hand, the tire mold opening/closing device  210  at the mold opening/closing station  200  moves in front of the tire mold assembly M 1 .  
         [0040]    (2) When the internal pressure supply device and the external pressure supply device for the tire mold assembly M 1  are disconnected, a mold receiving arn on the lower fixed plate  211  of the tire mold opening/closing device  210  is extended in the direction of the tire mold assembly M 1 , and is connected to the lower part of the tire mold assembly M 1 .  
         [0041]    (3) The mold receiving arm is retreated, and the tire mold assembly Ml slides on the guide roller group  102  at the vulcanizing station  100 . Then, the tire mold assembly Ml is transferred onto the guide roller group  214  on the lower fixed plate  211  and slides thereon, and is stopped at a predetermined position. At this time, the upper movable plate  206  lowers to a position slightly higher than the tire mold assembly M 1  and waits in such a manner as not to prevent the movement of mold.  
         [0042]    (4) After the tire mold assembly M 1  stops, the lower mold M 1   b  of the tire mold assembly M 1  is fixed to the lower fixed plate  211 , and at the same time, the upper movable plate  206  lowers and is connected to the upper mold M 1   a  of the tire mold assembly M 1 .  
         [0043]    (5) Simultaneously with the start of rise of the upper movable plate  206 , the cylinder  208  for the split mold operating device is operated, by which the upper mold M 1   a  begins to open. When the upper movable plate  206  continues to rise, the upper mold M 1   a  is opened fully, and reaches the upper limit position. The vulcanized tire T is left in the lower mold M 1   b.  The bladder operating mechanism  213  provided in the center of the lower fixed plate  211  is operated, so that the bladder BL is separated from the inside of tire.  
         [0044]    (6) The arm  403  of the unloader  400  enters the tire mold opening/closing device  210  at an appropriate time and lowers so that the holder  404  holds an upper bead portion of the vulcanized tire T in the lower mold M 1   b,  and rises, whereby the vulcanized tire T is carried out. The carried-out vulcanized tire T is placed on the tire delivery conveyor  500 .  
         [0045]    (7) The holder  304  of the loader  300  holds a green tire GT at an appropriate time, enters the tire mold opening/closing device  210 , and lowers, by which the green tire GT is mounted in the lower mold M 1   b.  The bladder operating mechanism  213  is operated, so that the bladder BL is inserted in the green tire GT.  
         [0046]    (8) The loader  300  releases the green tire GT at an appropriate time, rises, and retreats. Then, the upper movable plate  206  lowers, and the upper mold M 1   a  having being opened moves to the closing position.  
         [0047]    (9) After the completion of closing, the upper movable plate  206  and the upper mold M 1   a  are disconnected from each other, so that the upper movable plate  206  rises to a height such that the tire mold assembly M can pass through. On the other hand, the lower fixing plate  211  and the lower mold M 1   b  are disconnected from each other.  
         [0048]    (10) The mold receiving arm on the lower fixed plate  211  performs a pushing operation, so that the tire mold assembly M 1  on the lower fixed plate  211  is returned to the original position at the vulcanizing station  100 . The mold receiving arm and the tire mold assembly M 1  are disconnected from each other, so that the mold receiving arm is returned to the side of the lower fixed plate  211 .  
         [0049]    (11) The internal pressure supply device and the external pressure supply device are connected to the tire mold assembly at the vulcanizing station  100 , by which vulcanization is started. On the other hand, the tire mold opening/closing device  210  moves to a position in front of the tire mold assembly M to be operated next.  
         [0050]    For the tire vulcanizing system having the above-described configuration, the green tire supply apparatus and the vulcanized tire delivery conveyor are provided over the vulcanizing station on each side of the mold opening/closing station. Therefore, not only a green tire supply system using an aerial carrier can be used but also a green tire can be loaded by the loader before the unloader completely arrives at the retreat position.