JPS6113977B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in elastomeric articles, particularly forming drums such as carcass bands for bias tires.

In a conventional molding apparatus of this kind, as shown in FIG. It is designed to operate by pressing. The peripheral surface of the drum 1 itself is divided into a large number of segments a, b, c, d, e, f, as shown in FIG. For example, it is supported by a link mechanism so as to be displaced. In other words, the drum 1 has a foldable structure whose outer diameter expands and contracts. A carcass band 5 is formed by wrapping an unvulcanized rubber-covered cloth around the outer periphery of the drum 1 whose outer diameter expands and contracts, and pressing it with a roller 3 to vent air between the overlapped parts. Ru. The carcass band 5 that has completed its molding is removed from the drum 1 in a reduced diameter state and sent to the next process. However, drum 1
Even when the diameter of the carcass band 5 is reduced, there remains a part where the carcass band 5 and the drum 1 are in close contact with each other, and it takes time and effort to peel off this part and extract the carcass band 5 from the drum 1. .

The object of the present invention is to provide a band forming drum that eliminates the above-mentioned problems.

The structure of the present invention is that the forming drum is not made into a foldable structure, but three or more air chambers are provided inside the cylindrical drum surface portion, partitioned in the drum axial direction, and a small air chamber is provided that blows air from the air chambers onto the drum surface. After forming a carcass band, etc., a large number of holes are provided, and air is first blown out from the air chamber in the center in the axial direction of the drum, and then air is blown out sequentially from the air chambers outside of the air chamber. It is characterized by the fact that the surface that is in close contact with the product is raised and peeled off from the center in sequence toward both sides.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 4 shows the general structure of the molding drum, where 10 is a drum surface, 11, 12, 13, and 14 are air chambers, 15, 16, 17, and 18 are air pipes, and 19 is a control section.

The drum surface portion 10 is an integral true cylindrical body,
This has a large number of small holes 20 that penetrate inside and outside. The diameter of the small holes 20 is 1 to 2 mm, and the intervals are 10 to 30 mm in the axial direction of the drum and 50 to 100 mm in the circumferential direction of the drum.

The air chambers 11, 12, 13, and 14 are formed into an annular shape by providing an inner cylinder 21 at intervals inside the drum surface portion 10 and partitioning the space between them in the drum axial direction with partition walls 22, 23, 24, and 25. ing. Air chamber 11
is located at the center of the drum in the axial direction and is 1/1 of the total length of the drum.
The air chamber 12 is provided on both sides of the air chamber 11 and has a length of 1/10 of the total length of the drum, and air chambers 12 of the same length are provided on both sides of the drum. A chamber 13 is provided, and the remaining portions on both sides thereof are made into air chambers 14.

Incidentally, the above-mentioned examples of the lengths of each air chamber are, of course, only one example, and the present invention is not limited thereto.

The air pipes 15, 16, 17, 18 are provided so as to pass through the inside of the drum support shaft 26, and are branched midway to form each air chamber 11, 12, 12, 13, 13,
14, 14. The state of connection to each air chamber is such that the pipe ends are connected to each chamber at two locations on the inner surface of the inner cylinder 21 facing diametrically to the annular air chamber. Air pipe line 15,1
The other of 6, 17, and 18 is connected to a compressed air source 28 via a rotary joint 27 and a control section 19 at a position where it exits the drum support shaft 26.

The control unit 19 controls each of the pipes 15 and 1 branched into four directions from the compressed air source (6Kg/cm ² ) 28.
These are timer type electromagnetic on-off valves provided separately at 6, 17, and 18. The control section 19 is configured to sequentially open each electromagnetic valve 29 with a predetermined time difference in response to an appropriate starting signal after a predetermined carcass band molding is completed. That is, first, the solenoid valve 29 of the conduit 15 is opened, and then the solenoid valve 29 of the conduit 15 is opened.
The solenoid valve 29 of No. 6 is opened, then the solenoid valve of conduit 17 is opened, and finally the solenoid valve of conduit 18 is opened. After the carcass band is removed, the valve is returned to its original closed state.

The molding drum configured in this way is used in the same way as a conventional molding drum, and when a carcass band is molded by wrapping unvulcanized rubber cloth around its outer surface, the carcass band can be easily formed as follows. It can be taken out.

In other words, the carcass band that has been molded is
First, compressed air is supplied from the air pipe 15 to the air chamber 11 in the center, and air is blown out from the small holes 20 of the air chamber 11, causing the drum to be in close contact with the center of the drum. peels off, and an air layer of approximately 0.5 mm is formed between the drum surface and the carcass band. Next, the air chambers 1 on both sides
Compressed air is supplied to 2 and 12 from the air conduit 16, and air is similarly blown out from the small hole 20, causing the peeled portion to spread outward. Then, air is further supplied from the conduit 17 to the air chambers 13 on both outer sides, air is blown out from the small hole 20, the peeled part further expands, and finally air is supplied from the conduit 18 to the air chamber 14. When air is blown out from the small holes 20, the contact surface between the carcass band and the forming drum disappears. At this point, the carcass band is removed from the forming drum and sent to the next process.

As mentioned above, this molding drum sequentially blows air from the center in both directions from the entire surface of the drum, so that the separation of the surface in contact with the carcass band gradually expands from the center to the outside. As a result, there is no close contact between the molding drum and the carcass band, and the carcass band can be removed from the molding drum very easily. The reason why the air blowing position from the drum surface is expanded sequentially from the center to the outside is because, for example, if there are one or two air chambers, the air blowing will be concentrated at the outer edge and the carcass band will be This is because adhesion remains in parts other than both ends, making it impossible to achieve the objective. In addition, the central air chamber 1
The reason for increasing 1 is to shorten the time of the peeling process.

In the above embodiment, seven air chambers were formed, but this number may be increased or decreased, but three or more air chambers are required in the center and on both sides thereof.

In the above embodiment, the small holes 20 were simply formed on the drum surface, but in some cases, the air blown out from the small holes 20 may be given an outward direction so that the peeling area expands from the center to both outward directions. In order to achieve this, for example, as shown in FIG. 5, a shallow groove is provided along the circumferential direction on the outer peripheral surface of the molding drum, and the side walls of the groove are formed with an upright wall 30 on one side and a slope 31 on the other side. If a plurality of small holes are provided in the slope 31 in the circumferential direction, all the air is blown out from the center and directed outward, making it possible to achieve more effective peeling.

As described above, according to this invention, the forming drum does not have a folding structure as in the past, but instead has a structure in which air is appropriately blown from the surface of the molding drum while maintaining the predetermined cylindrical shape. Peeling and removal work can be performed reliably and easily in a short time.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the general configuration of a conventional band forming device, Fig. 2 is a schematic side view of a drum showing an example of the divided structure of a conventional forming drum, and Fig. 3 is an embodiment of the present invention. FIG. 4 is a partially enlarged perspective view showing another embodiment of the drum surface shape. 10...Drum surface portion, 11, 12, 13, 1
4... Air chamber, 15, 16, 17, 18... Air pipe line, 19... Control section, 20... Small hole.

Claims (1)

[Claims] 1. In a band forming drum for an elastomer article that is rotatably supported by a shaft and is formed by wrapping an unvulcanized rubber-covered material around the outer circumferential surface, the inside of the cylindrical drum surface is divided into three or more sections in the direction of the drum axis. An air chamber is provided, and an air pipe is provided to separately supply compressed air to each of the air chambers, and a large number of small air pipes are provided on the drum surface portion to communicate each of the air chambers with the drum surface. A band-forming drum for an elastomer article, comprising a control section having holes drilled therein and supplying compressed air sequentially from the center of the drum to the outside of the air chamber at appropriate time intervals.