JPH03189130A - Tire molding former - Google Patents

Abstract

PURPOSE:To make the title former simple in structure and applicable to a small-sized tire, by a method wherein a piston is fixed to a shaft having a flow path, a cylinder tube is put over the shaft and further each segment and the tube are connected by a rocking link with each other. CONSTITUTION:When a fluid such as air is fed into a cylinder tube 18 through a flow path 19 opening at a base end side of a piston 17, the cylinder tube 18 is moved to the base end side by resisting bouncing force of a bouncing member 22. The tube 18 abuts against a holding body 36 and segments S... each are in a state where the diameter is expanded most. Then when the fluid in the cylinder tube 18 is discharged through the flow path 19 under this state, the tube 18 is moved until the same abuts against a holding body 35 with the bounding force of the bouncing member 22. In this instance, also hinged points 0a, 0b of rocking links 9a, 9b... each and also hinged points 0a', 0b' of links 9a, 9b... each are moved, segments 1a, 1b each become a state where the diame ter is contracted and a cylindrical body 2 becomes a state where the diameter is contracted. On the contrary, when the fluid is fed into the cylinder tube 18 through the flow path 19, a state where the diameter is expanded is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tire forming former 5, particularly a so-called 2-
First former used in stage molding method
Regarding.

[Problems to be solved by conventional technology and invention] Conventionally, a two-stage molding method (first former) for green tires was used.
The first former in this method (a method in which a cylindrical tire carcass is formed using a second former and then shaved into a toroidal shape by a second former and integrated into a tread belt assembly to complete the forming of a green tire) is as follows:
For example, as shown in Fig. 6, a plurality of segments C are disposed along the circumferential direction of the inner shaft a via a link mechanism to form a cylindrical body d for molding. By rotating the inner shaft a by driving a motor, each segment C is displaced in the radial direction, thereby expanding or contracting the outer diameter of the cylindrical body d.

Therefore, in order to expand and contract, a tire molding machine with a double shaft and a shaft on which the inner ring rotates relative to the outer ring is required, which has the drawback that the gear box of the molding machine is complicated.

Therefore, an object of the present invention is to provide a molding former that has a simple structure and can be applied to small tires.

[Means to solve the problem]

In order to achieve the above object, the tire forming former according to the present invention is a tire forming former in which a cylindrical body having a plurality of segments arranged along the circumferential direction is attached so as to be displaceable in the radial direction. - in which a piston is fixed to a shaft, a cylinder tube having the piston therein is fitted onto the shaft so as to be able to reciprocate in the axial direction, and the cylinder tube is reciprocated in the axial direction; The shaft is provided with a flow passage for supplying and discharging fluid for the purpose, and furthermore, the shaft is provided with a flow path for supplying and discharging fluid for the purpose of the fluid. This is a cylinder tube and each segment connected.

[Operation] By simply supplying and discharging one system of fluid through the flow path in the cylinder tube, the cylinder reciprocates in the axial direction,
Due to the reciprocating motion, each segment is displaced in the radial direction, and the outer diameter of the cylindrical body is expanded or contracted.

〔Example〕

Hereinafter, the present invention will be explained in detail based on drawings showing examples.

1 and 2 show a tire forming former according to the present invention, and this former has a cylindrical body 2 in which a plurality of segments S are arranged along the circumferential direction, and a cylinder mechanism 4. The outer diameter of the cylindrical body 2 is expanded or contracted by being displaced in the radial direction through the cylindrical body 2.

Thus, the segments S are composed of two types of segments Ia and Ib (see FIGS. 3 and 4) each having an arcuate surface, an outer wall 5 and a main body 6 attached to the outer wall 5.
Further, the main body 6 has a distal end wall 7 and a proximal end wall 8, and as shown in FIGS. A pair of clamping pieces 10.
10 are provided on the distal and proximal sides of the inner surface 11. A shaft 13 is inserted through one end of the clamping piece 10.10 and the swing links 9a, 9b, and the one ends of the swing links 9a, 9b are pivotably attached to the segment S. 14 is a bush. Further, as shown in FIGS. 3 and 4, the circumferential length of the outer wall 5 of one segment 1a is set longer than the circumferential length of the outer wall 5 of the other segment 1b, and the outer walls of segments la and lb 5.5 side 15.15.16
．． 16 are respectively tapered surfaces, as shown in FIG.
In the expanded state, the adjacent side surfaces 15,16 are in contact. The outer wall 5 is composed of a distal end portion 5a, an intermediate portion 5b, and a proximal end portion 5c, and the outer wall 5 and the main body 6 are integrated with a fixing member 12 such as a bolt or nut.

Next, the cylinder mechanism 4 includes a piston 17 fixed to the shaft 3, a cylinder tube 18 that includes the piston, and supplies and discharges fluid to reciprocate the cylinder tube 18 in the axial direction. The flow path 19 is provided with a flow path 19, and the like.

Here, the piston 17 is made of a ring body and is fixed to a fixed ring 20 fixed to the shaft 3 via a bolt 21. Furthermore, a resilient member 22 holder 23 is connected to the fixing ring 20 .

Further, the cylinder tube 18 is composed of a distal wall section 24, a proximal wall section 25, and a circumferential wall section 26. , a clamping piece 27 that holds the other ends of the swing links 9a and 9b in a clamping manner.
27 are provided respectively. And the clamping piece 27.27
A shaft 28 is inserted through the other ends of the swing links 9a and 9b, and the other ends of the swing links 9a and 9b are pivotally connected to the cylinder tube 18 so as to be swingable. Reference numeral 29 denotes a bushing externally fitted onto the shaft 28, 30 a connector such as a bolt that connects the distal end wall 24 and the peripheral wall 26, and 31 a connector such as a bolt that connects the proximal wall 25 and the peripheral wall 26. It is a ingredient.

Further, the tip wall portion 24 is provided with through holes 32 arranged at a predetermined pitch in the circumferential direction, and a concave circumferential groove 33 is provided on the inner circumferential surface of the through hole 32 . , elastic member 2
The two end portions 22a are fitted together. Note that the elastic member 2
The base end portion 22b of No. 2 fits into the concave circumferential groove 34 of the holder 23. Therefore, the cylinder tube 18 is always elastically biased in the direction of arrow A.

Therefore, the flow path 19 opens toward the proximal end of the piston 17, and when fluid is supplied from the flow path 19 into the cylinder tube 18, the elastic force of the elastic member 22 as shown in FIG. Against this, the cylinder tube 18 moves toward the proximal end. Furthermore, when the fluid is discharged from the cylinder tube 18 through the flow path 19, the elastic force of the elastic member 22 causes the tube to
8 moves in the direction of arrow A.

Further, the shaft 3 is provided with a holder 35, 36 that holds each segment S, and each segment S is displaceable in the radial direction along the holder 35, 36.

Here, the holding body 35 includes a cylindrical portion 37a and a cylindrical portion 37a.
A main body 39 consisting of an outer flange 38a projecting outward from the
a, and a rod 40a fixed to the outer flange 38a of the main body 39a, and the rod 40a is fitted into a slide groove 41a provided in the tip wall 7 of the main body 6 of the segment S. Similarly, the holding body 36 also has a cylindrical portion 37b.
and an outer flange 38b protruding outward from the cylindrical portion 37b, and a rod 40b fixed to the outer flange 38b of the main body 39b.
is fitted into a slide groove 41b provided in the base end wall 8 of the main body 6 of the segment S. Therefore, each segment S
... is capable of sliding in the radial direction.

Therefore, the cylinder tube 1 of the swing links 9a and 9b
The pivot positions of the eight examples are made different between segment 1a and segment lb. That is, as shown in FIG. 5 (1),
The pivot point Ob on the cylinder tube 18 side of the swing link 9b to which the segment 1b is pivoted is moved a distance HLI closer to the tip than the pivot point Oa on the cylinder tube 18 side of the swing link 9a to which the segment la is pivoted. It is said that Therefore, if the swinging links 9a, 9b are moved by the distance in the direction of arrow A (horizontal direction) in FIG. 5(II) from the state shown in FIG. 5(1), each swinging link 9a, 9b Segment S side pivot points Oa, Ob” are in the direction of arrow B (vertical direction)
Move to. In this case, the pivot point Oa' and the pivot point ob' are offset by a distance jlft.

In other words, the pivot point Ob' of the swing link 9b is moved closer to the shaft 3 than the pivot point Oa'' of the swing link 9a, and the segment 1b is more compressed than the segment 1a, as shown in FIG. Also, when each swing link 9a, 9b starts moving in the direction of arrow A, the pivot point Oa
' and Ob' each begin to move in the direction of arrow B, but since the pivot point ob' moves more, the pivot point ob' moves faster. In other words, the movement of segment lb precedes the movement of segment 1a, and scaling is performed smoothly.

Next, a method of using the tire former constructed as described above will be described.

When fluid such as air is supplied into the cylinder tube 18 from the flow path 19, the cylinder tube 1
8 is in a state where it has moved toward the proximal end, as shown in FIG. 1, against the elastic force of the elastic member 22. In this state, the tube 18 is in contact with the holder 36, and each segment S is in its maximum diameter expanded state as shown in FIG. Then, if the fluid in the cylinder tube 18 is discharged from the flow path 19 from this state, the tube 18 will move as indicated by the arrow mark due to the elastic force of the elastic member 22.
The tube 18 moves in the direction until it comes into contact with the holder 35, resulting in the state shown in FIG. In this case, each swing link 9a.

The pivot points Oa and Ob of the links 9b, .

1b... becomes a reduced diameter state as shown in Fig. 4, and the cylindrical body 2
becomes a diameter-reduced state. Conversely, if fluid is supplied into the cylinder tube 18 through the flow path 19 from the state shown in FIGS. 2 and 4, the diameter will be expanded as shown in FIG. 1.

Note that the present invention is not limited to the above-described embodiments, and the design may be changed without departing from the gist of the present invention. For example, in the embodiment, the elastic member 22 is used as the cylinder mechanism 4. However, instead of this, it is also possible to form a flow path that opens toward the distal end side of the piston 17, and to supply and discharge fluid through the flow path. Further, the number of segments S of the cylindrical body 2 can be increased or decreased freely, and each segment S
It is also free to increase or decrease the number of swing links 9a, 9b.

Furthermore, the displacement distance between the pivot points of the swing links 9a and 9b can also be freely set.

〔Effect of the invention〕

Since the present invention is configured as described above, it has the following effects.

The piston 17 is fixed to the shaft 3 having a flow path, the cylinder tube 18 is placed on the shaft 3, and the tube 18 is connected to each segment with the swing link 9, so the overall mechanism is simple. In particular, the molding machine side is simple and easy to manufacture, the cost is not high, the outer diameter of the cylindrical body 2 can be reliably expanded and contracted, and the overall shape is compact. This has the advantage that it can be applied to the manufacture of small (small diameter) tires.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional front view of the main part in the expanded diameter state showing an embodiment of the present invention, Fig. 2 is a cross-sectional front view of the main part in the reduced diameter state, and Fig. 3 is an enlarged cross-sectional side view of the main part in the diameter enlarged state. , FIG. 4 is an enlarged cross-sectional side view of the main part in the reduced diameter state, and FIG. 5 is a front view of the swing link. FIG. 6 is a simplified side view showing a conventional example. 2... Cylindrical body, 3... Shaft, 9a, 9b... Rocking link, 17... Piston, I8... Cylinder tube, 19... Channel, S... Segment.

Claims (1)

[Claims] 1. In a tire forming former in which a cylindrical body 2 including a plurality of segments S arranged along the circumferential direction is mounted so as to be displaceable in the radial direction, a piston 17 is attached to the shaft 3.
A cylinder tube 18 having the piston 17 therein is externally fitted onto the shaft 3 so as to be capable of reciprocating in the axial direction, and in order to cause the cylinder tube 18 to reciprocate in the axial direction. Channel 1 for supplying and discharging fluid
9 is provided on the shaft 3, and the segments S of the cylindrical body 2 are displaced in the radial direction by the reciprocating movement of the cylinder tube 18 in the axial direction. A tire forming former characterized by connecting a cylinder tube 18 and each segment S.