Method and apparatus for vulcanising tyres

Abstract: A tire vulcanizing system of the present invention comprises a plurality of rows of tire vulcanizing stations (C11,C12,C13,C21,C22,C23) which contain a plurality of sets of movable tire mold assemblies (M11,M12,M13,M21,M22,M23) to vulcanize a tire; a mold opening/closing station (OP) which is disposed at the tire vulcanizing stations to receive the tire mold assembly to open and close a tire mold, by which a vulcanized tire is removed and a green tire is inserted; and a first mold transporting device (T1) and a second mold transporting device (T2) which are disposed between the mold opening/closing station and the tire vulcanizing stations to transport the tire mold assembly.

Description: The present invention relates to a tire vulcanizing system and a tire vulcanizing method, in which tire vulcanization, mold change, bladder change, mold preheating, and the like are carried out. In a conventional fully automatic tire vulcanizing press, the work time for loading a green tire, shaping, and unloading a vulcanized tire is far shorter than the time over which vulcanization is carried out 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 load/unload a tire and tire loading and unloading devices are low in operation efficiency. 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). As shown in FIGS. 7 and 8, this tire vulcanizing system comprises vulcanizing stations 501a and 501b, mold opening/closing stations 502a and 502b, tire mold transporters 503a and 503b, rails 504 for the tire mold transporters, mold beds 505a, 505b, . . . , an unloader 507a, a loader 508a, a conveyor 509a for conveying vulcanized tires, a rack 510a for green tires, and a mold changing station (for changing a tread mold, side wall mold, etc. in a tire mold assembly Ma to accommodate a change of specification of a tire to be vulcanized and for changing a bladder, which is an expendable) 511. In such a tire vulcanization system, a tire mold assembly Mc for which vulcanization has been finished is received by the tire mold transporter 503a (or 503b) from the vulcanizing station 501a (or 501b) at which a plurality of tire mold assemblies Mc being vulcanized are arranged, and is transported to the mold opening/closing station 502a (or 502b). After the tire mold assembly Mc having been transported to the mold opening/closing station 502a is connected to the tire mold opening/closing device 506a (or 506b), the tire mold assembly Mc is opened by the tire mold opening/closing device 506a, and a vulcanized tire is unloaded by the unloader 507a attached to the tire mold opening/closing device 506a. Then, a green tire is loaded by using the loader 508a attached to the tire mold opening/closing device 506a. After the loaded tire is shaped during a tire mold closing step and the tire mold assembly Mc is closed, a heating/pressurizing medium is introduced and sealed in the tire, by which a tire vulcanizing step is started. Next, the tire mold assembly Mc in which vulcanization has been started is disconnected from the tire mold opening/closing device 506a, placed on the tire mold transporter 503a again and transported, and returned to the vulcanizing station 501a, 501b ... In the above-described conventional tire vulcanizing system, a discharge device (a control valve and pipes) for discharging the heating/pressurizing medium in the bladder is provided at each vulcanizing station to shorten the operation time at the mold opening/closing station. Therefore, this system is undesirable from the economical viewpoint. In particular, this system is disadvantageous in terms of economy when this system, in which the control valve and pipes for vulcanization control are provided individually, is used for a facility for mass-producing tires having the equal vulcanization time. Also, when the conventional tire vulcanizing system is used for a production facility for small tires such as tires for a passenger car, for which the vulcanization time is as short as 8 to 12 minutes, this system requires the following. In this system, the time for which the mold transporting device receives a tire mold assembly at the vulcanizing station, the work at the mold opening/closing station is finished, and the closed tire mold assembly is transported again and returned to the vulcanization station must be as short as possible. The reason for this is that since the same mold transporting device is used for both ways, the time interval until the transportation of the next mold increases when the mold transporting device transports the mold assembly, so that there arise problems in that the number of molds constituting the tire vulcanizing system cannot be increased, and that the economical efficiency is decreased. From JP 10 146 838 A and JP 08 150 623 it is known to use one opening/closing station to unload vulcanized tires from and load green tires in mold assemblies coming from at least three or two rows of vulcanizing stations. Mold transporters, e.g. two, are arranged between adjacent mold rows to receive and supply molds to mold rows. The mold opening/closing devices are installed near the moving routes of the transporters. The arrangement of the transporters is such that in case of a breakdown of a transporter the tires vulcanized at a mold row cannot be removed This means everything must be strapped, causing damage on top of maintenance costs. The present invention has been made in view of the above situation, and accordingly an object thereof is to provide more economical tire vulcanizing system and tire vulcanizing method in which a discharge device is not disposed at each vulcanizing station, but is disposed at a position just before the mold loading side of a mold opening/closing station so as to be commonly used for a loaded mold assembly. Also, another object of the present invention is to provide more economical tire vulcanizing system and tire vulcanizing method in which a vulcanization control valve etc. is not disposed at each vulcanizing station, and a heating/pressurizing medium supply station is disposed on the mold unloading side of the mold opening/closing station so as to be commonly used for the supply of a heating/pressurizing medium into a bladder of a mold assembly unloaded from the mold opening/closing station and for the supply of a heating medium into a heating chamber outside the mold. Further, still another object of the present invention is to provide a more economical tire vulcanizing system in which a first transporter for transporting the tire mold assembly from a mold opening/closing device to a vulcanizing station and a second transporter for transporting the tire mold assembly from the vulcanizing station to the mold opening/closing device, by which the transportation time is shortened and the number of tire molds constituting the system is increased. For example, assuming that the vulcanization time is 10 minutes, the transporter reciprocating time is 40 seconds, and the treatment time at the mold opening/closing station is 80 seconds, in the case of the conventional system disclosed in Japanese Patent Provisional Publication No. 7-80846 (No. 80846/1995), the number of molds which can be treated by one mold opening/closing station is N1 = 10x60/(40+80) = 5 . . . 5 molds. By contrast, in the case of the system in accordance with the present invention, the number of molds which can be treated by one mold opening/closing station is N2 = 10x60/80 = 7.5 . . . 7 molds, and the number of molds which can be treated by first and second mold transporters is N3 = 10x60/40 = 15 . . . 15 molds. As the whole of the system, the number of molds which can be treated is 7 molds at a maximum. In the system in accordance with the present invention, the number of molds can be increased as compared with the conventional system disclosed in Japanese Patent Provisional Publication No. 7-80846. It can be found that in order to further increase the number of molds, the treatment capacity of the mold opening/closing station should be increased, as is apparent from the above calculation example. As one solution to this problem, two mold opening/closing stations have only to be arranged. However, this solution is undesirable in terms of economy. Thereupon, the applicant of the present invention proposes a vulcanizing system in which part of the operation process at the mold opening/closing station is carried out outside the mold opening/closing station, by which the treatment capacity of the mold opening/closing station is increased. Specifically, attention was paid to the fact that the treatment time of 80 seconds at the mold opening/closing station is composed of the following time: a) time for opening and closing the mold about 30 sec b) operation time of a vulcanized tire removing device about 10 sec c) bladder operating time for peeling a bladder off a vulcanized tire about 10 sec d) operation time of a green tire supply device about 10 sec e) time for inserting a bladder into a green tire and shaping it about 20 sec Thereby, the treatment capacity of the mold opening/closing station has been increased by eliminating about 30 seconds (time of the above items c and e) by the following means: A vulcanized tire, together with a bladder assembly, is separated from a mold and is moved to the outside of the mold opening/closing station. At this place, a bladder is peeled off the vulcanized tire. A bladder is inserted into a green tire and is shaped in another bladder assembly and tire in advance, and this is supplied to the mold immediately after the vulcanized tire and bladder assembly are separated from the mold. According to this method, trial calculation can be made as follows with the vulcanization time being 10 minutes in the same way as the above-described calculation example. The number of molds which can be treated by one mold opening/closing station N = 10x60/(80-30) = 12 12 molds The number of molds which can be treated by first and second mold transporters N = 10x60/40 = 15 15 molds As the whole of the system, the number of molds which can be treated is 12 molds at a maximum. Therefore, more economical tire vulcanizing system and tire vulcanizing method can be provided. The solution of the above-described problems with the conventional art is defined in the appended claims which are incorporated into the description by reference. The tire vulcanizing system in accordance with the invention comprises a plurality of rows of tire vulcanizing stations which contain a plurality of sets of movable tire mold assemblies to vulcanize a tire; a mold opening/closing station which is disposed at the tire vulcanizing stations to receive the tire mold assembly to open and close a tire mold, by which a vulcanized tire is removed and a green tire is inserted; and a first mold transporting device and a second mold transporting device which are disposed between the mold opening/closing station and the tire vulcanizing stations to transport the tire mold assembly. Also, the tire vulcanizing system in accordance with the invention (claim 2) comprises a plurality of rows of tire vulcanizing stations which contain a plurality of sets of movable tire mold assemblies to vulcanize a tire; a mold opening/closing station which is disposed at the tire vulcanizing stations to receive the tire mold assembly to open and close a tire mold, by which a vulcanized tire is removed and a green tire is inserted; and a first mold transporting device and a second mold transporting device which are disposed between the mold opening/closing station and the tire vulcanizing stations to transport the tire mold assembly, and further comprises a discharge station which is disposed on the mold loading side of the mold opening/closing station to discharge a heating/pressurizing medium in a bladder assembly of the tire mold assembly having been transported from the tire vulcanizing station; and a supply station which is disposed on the mold unloading side of the mold opening/closing station to supply the heating/pressurizing medium into a heating chamber and the bladder assembly of the tire mold assembly. Also, the present invention provides a tire vulcanizing method in which a movable tire mold assembly is carried onto a mold opening/closing station, where a tire mold is opened and closed to remove a vulcanized tire and insert a green tire for the vulcanization of tire, characterized in that a heating/pressurizing medium in a tire in the tire mold assembly is discharged at a waiting position just before the tire mold assembly is loaded to a mold opening/closing device at the mold opening/closing station, the tire mold is then opened and closed to remove the vulcanized tire and to insert the green tire, and the heating/pressurizing medium is supplied into the tire in the tire mold assembly and a heating medium is supplied to a heating chamber of the tire mold assembly at a waiting position on the unloading side of the tire mold assembly from the mold opening/closing device to vulcanize the tire. Therefore, the vulcanization of tire can be carried out more rapidly and economically. As described above, the tire vulcanizing system in accordance with the invention comprises a plurality of rows of tire vulcanizing stations which contain a plurality of sets of movable tire mold assemblies to vulcanize a tire; a mold opening/closing station which is disposed at the tire vulcanizing stations to receive the tire mold assembly to open and close a tire mold, by which a vulcanized tire is removed and a green tire is inserted; and a first mold transporting device and a second mold transporting device which are disposed between the mold opening/closing station and the tire vulcanizing stations to transport the tire mold assembly. Therefore, the transportation work of the tire mold assembly between the vulcanizing station and the mold opening/closing station can be performed independently at the same time, so that the productivity of the whole system can be enhanced by shortening the transportation time, and the number of tire molds constituting the vulcanizing system can be increased. Also, the tire vulcanizing system in accordance with the invention comprises a plurality of rows of tire vulcanizing stations which contain a plurality of sets of movable tire mold assemblies to vulcanize a tire; a mold opening/closing station which is disposed at the tire vulcanizing stations to receive the tire mold assembly to open and close a tire mold, by which a vulcanized tire is removed and a green tire is inserted; and a first mold transporting device and a second mold transporting device which are disposed between the mold opening/closing station and the tire vulcanizing stations to transport the tire mold assembly, and further comprises a discharge station which is disposed on the mold loading side of the mold opening/closing station to discharge a heating/pressurizing medium in a bladder assembly of the tire mold assembly having been transported from the tire vulcanizing station; and a supply station which is disposed on the mold unloading side of the mold opening/closing station to supply the heating/pressurizing medium into a heating chamber and the bladder assembly of the tire mold assembly. Therefore, the same effects as those of the above-described invention can be achieved, and also the heating/pressurizing medium discharge and supply stations can be commonly used for the loaded tire mold assembly. FIG. 1 is a plan view of a tire vulcanizing system in accordance with a first embodiment of the present invention; FIG. 2 is a view taken in the direction of the arrows along the line I-I of FIG. 1; FIG. 3 is a view taken in the direction of the arrows along the line II-II of FIG. 1; FIG. 4 is a plan view showing a tire vulcanizing method in accordance with one embodiment of the present invention and a tire vulcanizing system in accordance with a second embodiment for carrying out the same method; FIG. 5 is a view taken in the direction of the arrows along the line III-III of FIG. 4; FIG. 6 is a view taken in the direction of the arrows along the line IV-IV of FIG. 4; FIG. 7 is a plan view of a conventional tire vulcanizing system; and FIG. 8 is a front view of the conventional tire vulcanizing system. Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a plan view of a tire vulcanizing system in accordance with a first embodiment of the invention, FIG. 2 is a view taken in the direction of the arrows along the line I-I of FIG. 1, and FIG. 3 is a view taken in the direction of the arrows along the line II-II of FIG. 1. As shown in FIG. 1, the tire vulcanizing system in accordance with the first embodiment comprises a plurality of rows of tire vulcanizing stations C11 to C23 which contain a plurality of sets of movable tire mold assemblies M (M11 to M23) and vulcanize tires, a mold opening/closing station OP1 which is disposed at these vulcanizing station C11 to C23 to receive the tire mold assembly M to remove a vulcanized tire and insert a green tire by opening/closing the tire mold, and a first tire mold transporting device T1 and a second tire mold transporting device T2 which are disposed between the mold opening/closing station OP1 and the vulcanizing stations C11 to C23 to transport the tire mold assembly M. A first row of vulcanizing stations C11, C12 and C13 are arranged so that their centers are on a straight line, and a second row of vulcanizing stations C21, C22 and C23 are arranged in parallel with the first row. Although a total of six vulcanizing stations are arranged in this embodiment shown in FIG. 1, the number of vulcanizing stations may be increased, for example, by adding a third row. The vulcanizing stations C11 to c23 each have a plurality of sets of travel guide rollers Cf provided on a base (not shown) of the vulcanizing station. The tire mold assemblies M11, M12, M13, M21, M22 and M23 are arranged so as to be capable of being moved in the movement direction (for example, in the direction from the vulcanizing station C11 to C21) by means of these travel guide rollers Cf. Also, on the base of each of the vulcanizing stations C11 to C23, a positioning device (not shown) for positioning the mold assembly M having been moved is provided. By using this positioning device, the tire mold assembly M is fixed to a predetermined position, or it is released from its fixation. In addition, on the base of each of the vulcanizing stations C11 to C23, an internal pressure supply device and an external pressure supply device (if necessary, refer to Japanese Patent Provisional Publication No. 7-80846 (No. 80846/1995) published by the inventor of this invention), which are well-known and not shown in the figure, are provided. On one end side of the rows of the vulcanizing stations C11 to C23, a mold opening/closing device OP is provided. As shown in FIGS. 1 and 3, the mold opening/closing device OP comprises a frame OPa erected on a base OPj, a well-known loader OPg for loading a green tire which is capable of being moved vertically on a side surface of the frame OPa and swung between the center position of the mold opening/closing device (mold opening/closing station) OP1 and the waiting position, a well-known unloader OPh for unloading a vulcanized tire which is similar to the loader OPg and is disposed on the side surface of the frame OPa on the side opposite to the loader OPg, an elevation guide rail OPe provided on a side surface of the frame OPa other than the side surfaces on which the loader OPa and the unloader OPh are mounted, a guide bracket OPd sliding on the elevation guide rail OPe, an upper movable plate OPc fixed to the guide bracket OPd, a well-known split mold opening/closing operation device OPi provided at the center of the upper movable plate OPc, and a plurality of sets of elevating cylinders OPb one end of which is fixed to the frame OPa and the other end of which is fixed to the upper movable plate OPc. On the upper surface of the base OPj are provided guide rollers OPf and a positioning device (not shown) for positioning the tire mold assembly M having been moved, which are similar to those at the vulcanization stations C11 to C23. Also, at the central portion of the base OPj, that is, at the mold opening/closing station OP1, an operating device (not shown) for a bladder assembly (not shown) incorporated in the tire mold assembly M and an internal pressure supply device (not shown) for supplying a heating/pressurizing medium to the bladder assembly are provided. For the bladder assembly, the operating device for the bladder assembly, and the internal pressure supply device, which are not shown in the figures, Japanese Patent Provisional Publication No. 7-80846 (No. 80846/1995) published by the inventor of this invention should be referred to. On the other end side of the vulcanizing stations C11 to C23 (on the opposite side of the mold opening/closing device OP), a mold changing device MC and a mold preheating device PH are provided. The mold changing device MC has a structure similar to that of the mold opening/closing device OP, but it differs from the mold opening/closing device OP in that the loader OPg for loading a green tire, the unloader OPh for unloading a vulcanized tire, and the split mold opening/closing operation device OPi are not provided. That is to say, as shown in FIG. 2, the mold changing device MC comprises a frame MCa, an elevating cylinder MCb, an upper movable plate MCc, a guide bracket MCd, an elevation guide rail MCe, a travel guide rollers MCf, and the like. The mold preheating device PH comprises a base, travel guide rollers, an external pressure supply device, and a positioning device, like the vulcanizing station C11 to C23. On each side of the vulcanizing stations C11 to C23, the mold opening/closing device OP, the mold changing device MC, and the mold preheating device PH, the first tire mold transporting device T1 and the second tire mold transporting device T2 are provided. The first tire mold transporting device T1 (T1a, T1b, . .. ) can move between a stop position T10 at the front of the mold opening/closing device OP, stop positions T11, T12 and T13 at the front of the vulcanizing stations C11, C12 and C13, respectively, and a stop position T14 at the front of the mold changing device MC, and can stop as necessary. Also, the second tire mold transporting device T2 (T2a, T2b, . . . ) can move between a stop position T20 at the front of the mold opening/closing device OP, stop positions T21, T22 and T23 at the front of the vulcanizing stations C21, C22 and C23, respectively, and a stop position T24 at the front of the mold preheating device PH, and can stop as necessary. The first tire mold transporting device T1 and the second tire mold transporting device T2 have the same configuration. Therefore, only the first tire mold transporting device T1 will be described. The first tire mold transporting device T1 is provided with a base T1d along the vulcanizing stations C11, C12 and C13, and a plurality of sets of guide rollers Cf are provided on the base T1d. On these guide rollers Cf is provided a first tire mold transporter T1c, which can be moved along the vulcanizing stations C11, C12 and C13 by using a well-known driving unit T1a. On the top surface of the first tire mold transporter T1c are provided a plurality of sets of guide rollers T1b. The top level of the guide rollers T1b is set so as to have a height equal to that of the guide rollers OPf of the mold opening/closing device OP, the guide rollers Cf of the vulcanizing stations C11, C12 and C13, and the guide rollers MCf of the mold changing device MC. Further, the first tire mold transporter T1c is provided with a mold transfer device (not shown) which is used for transferring the mold assembly between the first tire mold transporter T1c and the mold opening/closing device OP or between the first tire mold transporter T1c and the vulcanizeing stations C11, C12 and C13. For this not illustrated mold transfer device, Japanese Patent Provisional Publication No. 8-192429 (No. 192429/1996) published by the inventor of this invention should be referred to. Also, for the details of the tire assembly, Japanese Patent Provisional Publication No. 8-47928 (No. 47928/1996) and Japanese Patent Provisional Publication No. 9-29746 (No. 29746/1997) published by the inventor of this invention should be referred to. Although the vulcanizing stations C11 to C23 of the first embodiment shown in FIG. 1 are arranged in two rows, the present invention is not limited to this configuration, and the vulcanizing stations C11 to C23 may be arranged in three rows, four rows, and so on. Also, the mold opening/closing device OP may be disposed at the intermediate portion of the vulcanizing stations. Next, the operation of the tire vulcanizing system in accordance with the first embodiment of the present invention will be described. (1) When the completion of tire vulcanization in the tire mold assembly at the vulcanizing station C21 is near at hand, a second tire mold transporter T2c moves to the stop position T21 at the front of the vulcanizing station C21, and stops there. (2) The internal pressure supply device and the external pressure supply device (both are not shown) are disconnected at the vulcanizing station C21. On the other hand, a mold receiving arm (not shown) on a table of the second tire mold transporter T2c is extended toward the vulcanizing station C21 and connected to a lower part of the tire mold assembly M21. (3) The mold receiving arm is withdrawn, so that the tire mold assembly M21 slides on the guide rollers Cf of the vulcanizing station C21, and then transfers onto the guide rollers T2b on the second tire mold transporter T2c and slides on them. When the tire mold assembly M21 comes to a predetermined position, it stops there. (4) When the tire mold assembly M21 stops, the lower part of the tire mold assembly M21 is fixed to the second tire mold transporter T2c. On the other hand, the second tire mold transporter T2c moves to the stop position T20 at the front of the mold opening/closing device OP and stops there. (5) After the second tire mold transporter T2c stops, the mold receiving arm of the second tire mold transporter T2c is extended toward the center of the mold opening/closing device OP. Then, the mold receiving arm is disconnected from the lower part of the tire mold assembly M21, and is withdrawn toward the second tire mold transporter T2c. Thereafter, the second tire mold transporter T2c moves to a stop position (T21, T22 or T23) at the front of the vulcanizing station at which the next vulcanization is to be finished, and waits there. (6) The upper movable plate OPc of the mold opening/closing device OP (OPa, OPb . . . ) waits at a position slightly higher than the tire mold assembly M21 in such a manner as not to obstruct the movement of the tire mold assembly M21 to be moved to under the upper movable plate OPc. (7) When the tire mold assembly M21 stops, the lower part of the tire mold assembly M21 is fixed. On the other hand, the upper movable plate OPc lowers and is connected to an upper part of the tire mold assembly M21. (8) Next, the upper movable plate OPc starts to rise, and at the same time, the split mold device (not shown) at the center of the upper movable plate OPc operates so that an upper mold starts to open. When the upper movable plate OPc continues to rise, the upper mold is opened fully and reaches the upper limit position. A vulcanized tire remains on a lower mold, and the bladder assembly (not shown) provided at the center of the tire mold assembly M21 is operated by a bladder driving device (not shown) provided at the center of the lower part of the mold opening/closing device OP, so that a bladder is peeled from the inside of the tire. (9) At an appropriate time, the unloader OPh advances and lowers, holds an upper bead portion of the vulcanized tire on the lower mold, and then rises and discharges the vulcanized tire. This discharged vulcanized tire is conveyed to the next process by using a discharge conveyor (not shown). (10) On the other hand, the loader OPg advances and lowers at an appropriate time while holding a green tire, and puts the green tire on the lower mold. Then, the bladder driving device is operated to insert a bladder into the green tire. (11) At an appropriate time, the loader OPg releases the green tire, and rises and retreats. Then, the upper movable plate OPc lowers so that the opened upper mold moves to the closing position. (12) After the upper mold is closed, the upper movable plate OPc is disconnected from the upper mold, and rises to a height such as to permit the passage of the tire mold assembly M21. On the other hand, the lower part of the mold assembly M21 is released. During the operation of the mold opening/closing device OP, the first tire mold transporter T1c waits at the stop position T10 on the exit side of the mold opening/closing device OP. (13) A mold receiving arm is extended from the first tire mold transporter T1c, and is connected to the lower part of the tire mold assembly M21. Then, the arm is withdrawn. The tire mold assembly M21 slides on the guide rollers OPf of the tire mold opening/closing device OP, and then transfers onto the guide rollers T1b on the first tire mold transporter T1c and slides on them. When the tire mold assembly M21 comes to a predetermined position, it stops there. (14) The lower part of the tire mold assembly M21 is fixed to the first tire mold transporter T1c, and the first tire mold transporter T1c moves along the vulcanizing stations and stops. The stop position is the stop position T11 at the front of the tire mold assembly M11 arranged abreast of the tire mold assembly M21 having been moved in items (1), (2) and (3) of the description of operation.After the tire mold assembly M21 is received by the second tire mold transporter T2c, the tire mold assembly M11 in which vulcanization is being performed is moved from the adjacent vulcanizing station C11 to the vulcanizing station C21 having become empty. Therefore, the vulcanizing station C11 on the side of the first tire mold transporter T1c is empty, so that it can receive the tire mold assembly M21 for which the predetermined work has been finished by the mold opening/closing device OP. (15) When the first tire mold transporter T1c stops at the stop position T11 at the front of the vulcanizing station C11, the tire mold assembly M21 is released. Then, the arm of the first tire mold transporter T1c is extended, so that the tire mold assembly M21 slides on the guide rollers T1b on the transporter, and then transfers onto the guide rollers Cf of the vulcanizing station C11 and slides on them, and stops. (16) After the tire mold assembly M21 stops, the arm is withdrawn toward the transporter, and the transporter moves to the position of the mold opening/closing device and stops for waiting. On the other hand, the tire mold assembly M21 stopping at the vulcanizing station is connected with the internal pressure supply device and the external pressure supply device, and a heating/pressurizing medium is supplied to continue the vulcanization of tire. When tires are manufactured, as shown in the above description of operation, the tire mold assembly M in which vulcanization has been finished is transported from the exit side of the vulcanizing station (C11 to C23) to the mold opening/closing device by using the second tire mold transporter T2c. After the predetermined work is finished, the tire mold assembly M is returned to the entrance side of the vulcanizing station by using the first tire mold transporting device, thereby continuing the vulcanization. When a tire mold device incorporated in the tire mold assembly M is changed during the production, the changing operation is performed by the following procedure. (1) For the tire mold assembly M in which the final vulcanization has been finished, after a vulcanized tire is removed by the procedure in items (1) to (9) in the above description of operation, the mold is closed without a green tire being inserted. (2) Subsequently, after the operation in items (12) and (13) is finished, the first tire mold transporter T1c moves along the vulcanizing stations, and stops at the stop position T14 at the front of the mold changing device MC. (3) When the first tire mold transporter T1c stops, the tire mold assembly M is released. Then, the arm of the first tire mold transporter T1c is extended, so that the tire mold assembly M slides on the guide rollers T1b on the transporter, transfers onto the guide rollers MCf of the mold changing device MC and slides on them, and stops at a center position MC1 of the mold changing device MC. (4) After the tire mold assembly M stops, the arm is disconnected from the lower part of the tire mold assembly M and withdrawn toward the transporter. Then, the tire mold transporter T1c moves and stops at the stop position T10 at the front of the mold opening/closing device OP for waiting. (5) When the tire mold assembly M stops, the lower part of the tire mold assembly M is fixed. (6) A worker engaging in the mold changing work removes connecting bolts for connecting the tire mold device to upper and lower plates of the tire mold assembly M like the work on the conventional vulcanizer. (7) Thereafter, an upper plate of the mold changing device MC lowers and is connected to the upper plate of the tire mold assembly M. When the upper plate is raised, the tire mold device is left on the lower side. (8) The worker takes out the used tire mold device by using a forklift or the like equipment, and loads and sets a new tire mold device prepared in advance. (9) The upper movable plate MCc lowers and puts the upper plate of the mold assembly M on the new tire mold device. After the upper movable plate MCc rises, the worker installs the bolts having been removed in item (6). (10) Subsequently, the tire mold assembly M moves to a position of the adjacent mold preheating device PH, and stops. After stopping, the tire mold assembly M is connected with the external pressure supply device to supply a heating medium, by which the heating of the tire mold is started. (11) The mold assembly M heated to a predetermined temperature is transported to the mold opening/closing device OP by using the second tire mold transporter T2c at an appropriate time, and the mold is opened. Then, a green tire is supplied, by which the tire production is started. If the number of tire mold assemblies is set so that extra one for preheating is added to the number of vulcanizing stations (six in the example shown in the figures), the tire mold assembly to be changed can be prepared during the tire production, and after the used mold assembly has been carried out, the tire production can be started immediately by using a new mold. FIGS. 4 to 6 show a tire vulcanizing method in accordance with one embodiment of the present invention and a tire vulcanizing system in accordance with a second embodiment for carrying out the same method. FIG. 4 is a plan view thereof, FIG. 5 is a view taken in the direction of the arrows along the line III-III of FIG. 4, and FIG. 6 is a view taken in the direction of the arrows along the line IV-IV of FIG.4. As shown in FIG. 4, the tire vulcanizing system in accordance with the second embodiment comprises a plurality of rows of tire vulcanizing stations C11 to C34 which contain a plurality of sets of movable tire mold assemblies M (M11 to M33) and vulcanize tires, a mold opening/closing station OP1 which is disposed at these vulcanizing station C11 to C34 to receive the tire mold assembly M to remove a vulcanized tire T and insert a green tire GT by opening/closing the tire mold, and a first tire mold transporting device T1 and a second tire mold transporting device T2 which are disposed between the mold opening/closing station OP1 and the vulcanizing stations C11 to C34 to transport the tire mold assembly M. The vulcanizing system further comprises a discharge station OP2 which is disposed on the mold loading side of the mold opening/closing station OP1 to discharge a heating and pressurizing medium in a bladder assembly of the tire mold assembly M having been transported from the tire vulcanizing station C11 to C34, and a supply station OP3 for supplying the heating and pressurizing medium to a heating chamber of the tire mold assembly M and into the bladder assembly. A first row of vulcanizing stations C11, C12, C13 and C14 are arranged so that their centers are on a straight line, and a second row of vulcanizing stations C21, C22, C23 and C24 are arranged in parallel with the first row, and further a third row of vulcanizing stations C31, C32, C33 and C34 are arranged. Although a total of twelve vulcanizing stations are arranged in this embodiment shown in FIG. 4, the number of vulcanizing stations may be increased, for example, by adding C15, C25 and C35. The vulcanizing stations C11 to C34 each have a plurality of sets of travel guide rollers Cf provided on a base Co of the vulcanizing station. The tire mold assemblies M11 to M33 are arranged so as to be capable of being moved in the movement direction (for example, in the direction from vulcanizing station C11 to C21, or in the direction from C21 to C31) by means of these travel guide rollers Cf. Since the tire mold assembly moves during operation, it cannot be specified in FIG. 4 which of the mold assemblies is M11. Therefore, M11 is typically indicated as a mold assembly M at the vulcanizing station C11 in FIG. 4. Also, on the base of each of the vulcanizing stations C11 to C34, a positioning device (not shown) for positioning the mold assembly M having been moved is provided. By using this positioning device, the tire mold assembly M is fixed to a predetermined position, or it is released from its fixation. On one end side of the rows of the vulcanizing stations C11 to C34, a mold opening/closing device OP is provided. As shown in FIGS. 4 and 6, the mold opening/closing device OP comprises a frame OPa erected on a base OPj, a well-known loader OPg for loading a green tire GT which is capable of being moved vertically on a side surface of the frame OPa and swung between the center position of the mold opening/closing device (mold opening/closing station) OP1 and the waiting position, a well-known unloader OPh for unloading a vulcanized tire T which is similar to the loader OPg and is disposed on the side surface of the frame OPa on the side opposite to the loader OPg, an elevation guide rail OPe provided on a side surface of the frame OPa other than the side surfaces on which the loader OPa and the unloader OPh are mounted, a guide bracket OPd sliding on the elevation guide rail OPe, an upper movable plate OPc fixed to the guide bracket OPd, a well-known split mold opening/closing operation device OPi provided at the center of the upper movable plate OPc, and a plurality of sets of elevating cylinders OPb one end of which is fixed to the frame OPa and the other end of which is fixed to the upper movable plate OPc. On the upper movable plate OPc, a mold connecting device OPk is provided to connect and disconnect the upper movable plate OPc to and from an upper plate Ma of the tire mold assembly M. On the upper surface of the base OPj are provided guide rollers OPf and a positioning device (not shown) for positioning the tire mold assembly M having been moved, which are similar to those at the vulcanization stations C11 to C34. Also, at the central portion of the base OPj, that is, at the mold opening/closing station OP1, an operating device (not shown) for a bladder assembly (not shown) incorporated in the tire mold assembly M and an internal pressure piping connecting device (not shown) for supplying a vacuum pressure and preshaping medium to the bladder assembly are provided. At an intermediate position between the mold opening/closing station OP1 on the base OPj and a stop position T20 of the second tire mold transporting device T2, a heating/pressurizing medium discharge station OP2 is provided which has an internal pressure piping connecting device (not shown) for discharging a heating/pressurizing medium in the bladder assembly of the mold assembly M having been moved. Also, at an intermediate position between the mold opening/closing station OP1 on the base OPj and a stop position T10 of the first tire mold transporting device T1, a heating/pressurizing medium supply station OP3 is provided which has an internal pressure piping connecting device (not shown) for supplying a heating/pressurizing medium into the bladder assembly of the mold assembly M having been delivered from the mold opening/closing station OP1 and an external pressure piping connecting device (not shown) for supplying a heating medium into an external heating chamber of the mold assembly M. These internal pressure piping connecting device and external pressure piping connecting device have been disclosed in Japanese Patent Provisional Publication No. 7-80846(No. 80846/1995) published by the inventor of this invention. On the other end side of the vulcanizing stations (on the opposite side of the mold opening/closing device OP), a mold changing device MC and a mold preheating device PH are provided. The mold changing device MC has a structure similar to that of the mold opening/closing device OP, but it differs from the mold opening/closing device OP in that the loader OPg for loading a green tire GT, the unloader OPh for unloading a vulcanized tire T, and the split mold opening/closing operation device OPi are not provided. That is to say, as shown in FIGS. 4 and 5, the mold changing device MC comprises a frame MCa, an elevating cylinder MCb, an upper movable plate MCc, a guide bracket MCd, an elevation guide rail MCe, a travel guide rollers MCf, a base MCj, and a mold connecting device MCk. The mold preheating device PH is provided at an intermediate position (preheating station) PH1 between a mold changing station MC1 and a stop position T25 of the second tire mold transporting device T2. Also, a mold waiting station MC2 is provided at an intermediate position between the mold changing station MC1 and a stop position T15 of the first tire mold transporting device T1. On the base MCj are provided the travel guide rollers MCf and positioning devices (not shown) at station positions MC1, MC2 and PH1. The preheating station PH1 is provided with an external piping connecting device (not shown). On each side of the vulcanizing stations C11 to C14, C21 to C24, and C31 to C34, the mold opening/closing device OP, the mold changing device MC, and the mold preheating device PH, the first tire mold transporting device T1 and the second tire mold transporting device T2 are provided. The first tire mold transporting device T1 can move between the stop position T10 at the front of the heating/pressurizing medium supply station OP3, stop positions T11, T12, T13 and T14 at the front of the vulcanizing stations C11, C12, C13 and C14, respectively, and the stop position T15 at the front of the mold waiting station MC2, and can stop as necessary. Also, the second tire mold transporting device T2 can move between the stop position T20 at the front of the heating/pressurizing medium discharge station OP2, stop positions T21, T22, T23 and T24 at the front of the vulcanizing stations C31, C32, C33 and C34, respectively, and the stop position T15 at the front of the mold preheating station PH1, and can stop as necessary. The first tire mold transporting device T1 and the second tire mold transporting device T2 have the same configuration. Therefore, only the first tire mold transporting device T1 will be described. The first tire mold transporting device T1 is provided with a base T1d along the vulcanizing stations C11, C12, C13 and C14, and a plurality of sets of guide rollers T1f are provided on the base T1d. On these guide rollers T1f is provided a first tire mold transporter T1c, which can be moved along the vulcanizing stations C11, C12, C13 and C14 by using a well-known driving unit T1a. On the top surface of the first tire mold transporter T1c are provided a plurality of sets of guide rollers T1b. The top level of the guide rollers T1b is set so as to have a height equal to that of the guide rollers OPf on the base OPj, the guide rollers Cf of the vulcanizing stations C11, C12, C13 and C14, and the guide rollers MCf on the base MCj. Also, the first tire mold transporter T1c is provided with a mold transfer device (not shown) which is used for transferring the mold assembly M between the first tire mold transporter T1c and the heating/pressurizing medium supply station OP3 or between the first tire mold transporter T1c and the vulcanizing stations C11, C12, C13 and C14. For this not illustrated mold transfer device, Japanese Patent Provisional Publication No. 8-192429 (No. 192429/1996) published by the inventor of this invention should be referred to. Also, for the details of the tire assembly, Japanese Patent Provisional Publication No. 8-47928 (No. 47928/1996) and Japanese Patent Provisional Publication No. 9-29746 (No. 29746/1997) published by the inventor of this invention should be referred to. Next, the tire vulcanizing method in accordance with one embodiment of the present invention and the operation of the tire vulcanizing system in accordance with the second embodiment for carrying out the same method will be described. (1) When the completion of tire vulcanization in the tire mold assembly M32 at the vulcanizing station C32 is near at hand, a second tire mold transporter T2c moves to the stop position T22 at the front of the vulcanizing station C32, and stops there. (2) A mold receiving arm on a table of the second tire mold transporter T2c is extended toward the vulcanizing station C32 and connected to a lower part of the tire mold assembly M32. (3) The mold receiving arm is withdrawn, so that the tire mold assembly M32 slides on the guide rollers Cf of the vulcanizing station C32, and then transfers onto the guide rollers T2b on the second tire mold transporter T2c and slides on them. When the tire mold assembly M32 comes to a predetermined position, it stops there. (4) When the tire mold assembly M32 stops, the lower part of the tire mold assembly M32 is fixed to the second tire mold transporter T2c. On the other hand, the second tire mold transporter T2c moves to the mold opening/closing device OP side and stops at the stop position T20. (5) After the second tire mold transporter T2c stops, the mold receiving arm of the second tire mold transporter T2c is extended toward the center of the discharge station OP2. Then, the mold receiving arm is disconnected from the lower part of the tire mold assembly M32, and is withdrawn toward the second tire mold transporter T2c. Thereafter, the second tire mold transporter T2c moves to a stop position (T21, T22 or T23) at the front of the vulcanizing station at which the next vulcanization is to be finished, and waits there.On the other hand, when the mold assembly M32 stops at the position of the discharge station OP2, an internal pressure discharge device is connected, by which the heating/pressurizing medium in the bladder assembly of the tire mold assembly M32 is discharged. The tire mold assembly M32 waits until the time when the mold opening/closing device OP can receive the mold assembly. (6) In the mold opening/closing device OP, the tire mold assembly brought to the front of the mold assembly M32 having been subjected to a predetermined work is discharged to the heating/pressurizing medium supply station OP3. Also, the upper movable plate OPc of the mold opening/closing device OP waits at a position slightly higher than the tire mold assembly M32 in such a manner as not to obstruct the movement of the tire mold assembly M32 to be moved to under the upper movable plate OPc. (7) When the tire mold assembly M32 stops at the center position (mold opening/closing station) OP1 of the mold opening/closing device OP, the lower part of the tire mold assembly M32 is fixed. On the other hand, the upper movable plate OPc lowers and is connected to an upper part of the tire mold assembly M32. (8) Next, the upper movable plate OPc starts to rise, and at the same time, the split mold device (not shown) at the center of the upper movable plate OPc operates so that an upper mold starts to open. When the upper movable plate OPc continues to rise, the upper mold is opened fully and reaches the upper limit position. A vulcanized tire T remains on a lower mold, and the bladder assembly (not shown) provided at the center of the lower mold of the tire mold assembly is operated by a bladder driving device (not shown) provided at the center of the lower part of the mold opening/closing device OP, so that a bladder B is peeled from the inside of the tire. (9) At an appropriate time, the unloader OPh advances and lowers, holds an upper bead portion of the vulcanized tire T on the lower mold, and then rises and discharges the vulcanized tire T. This discharged tire is conveyed to the next process by using a discharge conveyor (not shown). (10) On the other hand, the loader OPg advances and lowers at an appropriate time while holding a green tire GT, and puts the green tire GT on the lower mold. Then, the bladder driving device is operated to insert a bladder B into the green tire GT. At an appropriate time, the loader OPg releases the green tire GT, and rises and retreats. (11) Then, the upper movable plate OPc lowers so that the opened upper mold moves to the closing position. After the upper mold is closed, the upper movable plate OPc is disconnected from the upper mold, and rises to a height such as to permit the passage of the tire mold assembly M32. On the other hand, the lower part of the mold assembly M32 is released.The mold assembly M32 moves and stops at the heating/pressurizing medium supply station OP3, where an internal pressure supply device and an external pressure supply device are connected to the tire mold assembly M32, by which the heating/pressurizing medium is supplied and the vulcanization of tire is started.This heating/pressurizing medium is in a state such as to be confined by a check valve provided on the mold assembly. During the above-described operation, the first tire mold transporter T1c waits at the stop position T10. (12) A mold receiving arm is extended from the first tire mold transporter T1c, and is connected to the lower part of the tire mold assembly M32. Then, the arm is withdrawn. The tire mold assembly M32 slides on the guide rollers OPf, and then transfers onto the guide rollers T1b on the first tire mold transporter T1c and slides on them. When the tire mold assembly M32 comes to a predetermined position, it stops there. (13) The lower part of the tire mold assembly M32 is fixed to the first tire mold transporter T1c, and the first tire mold transporter T1c moves along the vulcanizing stations and stops. The stop position is the stop position T12 at the front of the tire mold assembly M12 arranged abreast of the tire mold assembly M32 having been moved in items (1), (2) and (3) of the description of operation.After the tire mold assembly M32 is received by the second tire mold transporter T2c, the tire mold assembly M22 in which vulcanization is being performed is moved from the adjacent vulcanizing station C22 to the vulcanizing station C32 having become empty. Then, the tire mold assembly M12 in which vulcanization is being performed is moved from the vulcanizing station C12 to the vulcanizing station C22.Therefore, the vulcanizing station C12 on the side of the first tire mold transporter T1c is empty, so that it can receive the tire mold assembly M32 for which the predetermined work has been finished by the mold opening/closing device OP. (14) When the first tire mold transporter T1c stops at the stop position T12 at the front of the vulcanizing station C12, the tire mold assembly M32 is released. Then, the arm of the first tire mold transporter T1c is extended, so that the tire mold assembly M32 slides on the guide rollers T1b on the transporter, and then transfers onto the guide rollers Cf of the vulcanizing station C12 and slides on them, and stops. (15) After the tire mold assembly M32 stops, the arm is withdrawn toward the transporter, and the transporter moves to the position T10 of the mold opening/closing device side and stops for waiting until it receives the next mold assembly. For the tire vulcanizing system in accordance with the second embodiment of the invention, the operation in producing tires and the procedure for changing a tire mold device during the production are the same as those in the first embodiment.

Claims: Tire vulcanizing system comprising a plurality of rows of tire vulcanizing stations (C11-C34) which rows contain a plurality of sets of movable tire mold assemblies (M11-M33) to vulcanize a tire; a mold opening/closing station (OP) which is disposed at one row end side of the plurality of rows of the tire vulcanizing stations (C11-C34) to receive a tire mold assembly (M) to open and close a tire mold for removing a vulcanized tire (T) and inserting a green tire (GT), and mold transporting means disposed alongside of the plurality of rows of tire vulcanizing stations (C11-C34) for transporting the mold assemblies to and from the mold opening/closing station (OP), characterized by a first mold transporting device (T1) which is disposed along one side of the plurality of rows of tire vulcanizing stations (C11-C34) and a second mold transporting device (T2) which is disposed on the other side of the plurality of rows of tire vulcanizing stations (C11-C34); the first mold transporting device and the second mold transporting device are provided on each side of the mold opening/closing device and the vulcanizing stations, the tire mold assembly (M) is transported to the mold opening/closing station (OP) by using the first mold transporting device (T1), the tire mold assembly (M) charged with a green tire is transferred from the mold opening/closing station (OP) onto the second mold transporting device (T2), and the tire mold assembly (M) is transported to the other side of the tire vulcanizing station (C) by using the second mold transporting device (T2). Tire vulcanizing system according to claim 1, further comprising a discharge station (OP2) which is disposed on the mold loading side of the mold opening/closing station (OP) to discharge a heating/pressurizing medium in a bladder assembly of the tire mold assembly (M) having been transported from the tire vulcanizing station (C); and a supply station (OP3) which is disposed on the mold unloading side of the mold opening/closing station (OP) to supply heating/pressurizing medium into a bladder assembly and a heating medium into a heating chamber of the tire mold assembly (M). Tire vulcanizing system according to claim 1 or 2, wherein, while the mold opening/closing station (OP) is disposed on the one row end side of the plurality of rows of tire vulcanizing stations (C11-C34), a mold changing device (MC) and a mold preheating device (PH) are disposed on the other row end side of the tire vulcanizing stations (C11-C34). Tire vulcanizing method in which a movable tire mold assembly (M) is carried from a plurality of rows of tire vulcanizing stations (C11-C34) which rows contain a plurality of sets of movable tire mold assemblies (M11-M33) to vulcanize a tire, to and from a mold opening/closing station (OP), where a tire mold is opened and closed for removing a vulcanized tire (T) and inserting a green tire (GT) for the vulcanization of that green tire, characterized in that the mold assemblies (M) are carried from one row of the plurality of rows of vulcanizing stations by a first mold transporting device (T1) which is disposed along the one side of the plurality of rows of tire vulcanizing stations (C11-C34) to the mold opening/closing station (OP) being disposed at one row end side of the rows of vulcanizing stations (C11-C34), a heating/pressurizing medium in a tire in the tire mold assembly (M) is discharged at a waiting position just before the tire mold assembly (M) is loaded to a mold opening/closing device (OP1) at the mold opening/closing station (OP), and heating/pressurizing medium is supplied into the tire in the heating/vulcanizing assembly and a heating medium is supplied to a heating chamber of the tire mold assembly (M) charged with the green tire at a waiting position on the unloading side of the tire mold assembly (M) from the mold opening/closing device (OP1) to vulcanize the tire, the tire mold assembly (M) is transferred from the mold opening/closing station (OP) after having been discharged therefrom onto a second mold transporting device (T2) which is disposed on the other side of the plurality of rows of tire vulcanizing stations (C11-C34), and the tire mold assembly (M) is transported to the other side of the tire vulcanizing station (C) by using the second mold transporting device (T2).

Inventors: IRIE NOBUHIKO, IRIE, NOBUHIKO, Irie, Nobuhiko, Nagasaki Shipyard&amp;Machinery Works
Applicants: MITSUBISHI HEAVY IND LTD, MITSUBISHI HEAVY INDUSTRIES, LTD.
Application year: 1999
Main classification: B29D30
IPC codes: B29C33, B29C35, B29D30, B29K21, B29K105, B29L30