Inner tube joint die

Abstract

The utility model provides an inner tube joint mould, which comprises a lower opening mould for bearing an inner tube joint and an upper opening mould separably pressed against the inner tube joint, the lower opening mould is an elastic colloid mould, the bottom of the wall side of the lower opening mould crumples inwards to form a limiting groove for embedding the inner tube joint, and the upper opening mould is an elastic rubber mould. An impedance baffle is embedded in the side edge, away from the center direction of the lower opening mold, of the limiting groove, and when the inner tube connector arranged in the limiting groove has the deformation tendency of radial extension under the pressing of the upper opening mold, the impedance baffle supports the limiting groove and provides acting force opposite to the extension direction. The problems of tire body deformation at the joint part, joint dislocation and the like are solved, and meanwhile the joint strength is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of wheel accessories and manufacturing, in particular to an inner tube joint die. Background Art

[0002] A tire mainly consists of an outer tire, an inner tube and a flap. Among them, the inner tube is an annular rubber tube used to maintain the internal pressure of the tire and is equipped with a tire valve. The inner tube is an important part of the tire and needs to have characteristics such as good airtightness, heat resistance, elasticity, aging resistance and small permanent deformation. The inner tube joint die is used for the butt joint of the inner tube rubber tube of the tire. The extruder extrudes an inner tube rubber tube in the shape of a tubular rubber hose, and the inner tube joint die butt-joints the inner tube rubber tube extruded by the extruder into an annular inner tube. Since the butt joint of the inner tube rubber tube joint needs to be carried out under high pressure, when cutting the tire tube and butt-jointing the joint, due to the large pressure of the pressing foot, problems often occur such as the two sides of the flattened tire tube extending outwards due to the increase in the pressure received by the local part of the tire tube, and different extension degrees resulting in deformation of the tire body at the joint part and dislocation of the joint. Content of the Utility Model

[0003] In view of this, the purpose of the utility model is to provide an inner tube joint die to overcome the inner tube rubber tube joint.

[0004] To solve the above technical problems, the utility model provides an inner tube joint die, which includes a lower die for supporting the inner tube joint and an upper die that can be detachably pressed against the inner tube joint. The lower die is an elastic rubber die, and the bottom of its wall side collapses inwards to form a limiting groove for embedding the inner tube joint.

[0005] An impedance baffle is embedded on the side of the limiting groove away from the center direction of the lower die. When the inner tube joint arranged in the limiting groove has a tendency to radially extend under the pressing of the upper die, the impedance baffle supports the limiting groove and provides a force against the extending direction.

[0006] In a preferred embodiment: the impedance baffle includes a first part extending along the width direction of the limiting groove and a second part extending along the depth direction of the limiting groove, and the first part and the second part are rigidly connected.

[0007] In a preferred embodiment: the impedance baffle is in clearance fit with the limiting groove.

[0008] In a preferred embodiment: the width of the limiting groove is twice the wall thickness of the inner tube joint.

[0009] In a preferred embodiment: the first part and the second part are made of a metal material with a predetermined stiffness, and the connection angle between the two is a right angle.

[0010] In a preferred embodiment: the rigid connection is welding.

[0011] In a preferred embodiment, the cross-sectional shape of the limiting groove is semi-circular arc-shaped, and the arc edge of the semi-circular arc is tangent to the bottom surface of the lower die.

[0012] Compared with the prior art, the technical solution of the present utility model has the following beneficial effects:

[0013] The present utility model provides an inner tube joint die. By embedding an impedance baffle on the side of the limiting groove of the lower die mouth, when the inner tube joint arranged in the limiting groove has a deformation tendency of radial extension under the pressing of the upper die mouth, the impedance baffle supports the limiting groove and provides a force in the reverse direction of the extension to prevent the deformation of the carcass at the joint part and the problem of dislocation of the joint, so as to improve the joint strength. Description of the Drawings

[0014] Figure 1 is a side view of the existing lower die;

[0015] Figure 2 is a force diagram of the existing lower die in the molding state;

[0016] Figure 3 is a side view of the lower die of the present utility model;

[0017] Figure 4 is a force diagram of the lower die seat of the present utility model. Detailed Embodiments

[0018] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model; obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0019] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "top / bottom end", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0020] In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "installed / connected", "connected", etc. should be understood in a broad sense. For example, "connection" can be a wall-mounted connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0021] The inner tube joint machine is a special equipment for connecting the tire blank of the pneumatic inner tube into a semi-finished product for vulcanization. At present, the inner tube joint machines commonly used in China are mostly mechanical and hydraulic (or pneumatic) joint machines. Its operation mode is to clamp the tire blank in the die die for cutting, leaving a certain distance outside the buffer die during cutting, and then close the two die dies, bond the tire blank and then vulcanize it to form the inner tube finished product. However, when the inner tube joint machine commonly used at present presses the pneumatic inner tube tire blank into a semi-finished product, because the die die adopts a rectangular die die, the pneumatic inner tube tire blank has clearance at the four corners when entering the die die. When the upper die 11 is matched with the lower die 12, it is easy to produce the tire blank with undesirable conditions such as crushing, wrinkling and edge escape, resulting in a high defective rate of the product. In order to prevent the tire blank from being crushed in the prior art, a flexible base is often used to fix the inner tube tire blank. The flexible base of the lower die 12 is usually an elastic colloid die, which can achieve the purpose of buffering pressure by deforming its own elastic material when resisting radial extrusion of the upper die 11. Figure 1-2 However, since the tire blank and the lower die 12 of the inner tube are both made of elastic materials and have the ability to elastically deform to adapt to different pressures, it is easy to cause the tire blank and the lower die 12 to be compressed at the same time during actual processing, resulting in the flat tire barrel and both sides of the lower die 12 extending outward to different degrees. The different ductility of the materials of the two materials leads to different elongation, which in turn causes the tire body at the joint to be deformed and misaligned to different degrees.

[0022] In view of this, the utility model proposes an inner tube joint mold 21 based on the above working conditions, wherein the joint mold includes a lower mold 12 for receiving the inner tube joint 21, and an upper mold 11 detachably pressed against the inner tube joint 21, the bottom of the wall side of the lower mold 12 collapses inward to form a limiting groove for embedding the inner tube joint 21, and an impedance baffle 121 is embedded in the side of the limiting groove away from the center direction of the lower mold 12. When the inner tube joint 21 arranged in the limiting groove has a radially extending deformation tendency under the pressure of the upper mold 11, the impedance baffle 121 supports the limiting groove and provides a force in the opposite direction of the extension, thereby blocking the inner tube joint 21 from extending and deforming outward, thereby ensuring the bonding strength of the inner tube joint 21.

[0023] From a microscopic structure perspective, the cross-sectional shape of the limiting groove is semi-circular arc-shaped. The arc side of the semi-circular arc is tangent to the bottom surface of the lower die 12. Its groove width is twice the wall thickness of the inner tube joint 21, and its groove depth is less than the groove width. An impedance baffle 121 is embedded at a position spaced a predetermined distance from the center line of the lower die 12 along the groove depth direction. The impedance baffle 121 is in clearance fit with the limiting groove and its composition includes a first part extending along the width direction of the limiting groove and a second part extending along the depth direction of the limiting groove. In order to ensure that the impedance baffle can stably and reliably provide a pushing force for the adjacent limiting groove, in this embodiment, the first part and the second part constituting the impedance baffle 121 are made of a metal material with a predetermined stiffness. Considering the force stability, the connection angle between the two is set to a right angle and rounded at the corners, and they are connected by welding.

[0024] From the perspective of force transmission, the upper die 11 presses radially downward under the action of the cylinder against the inner tube joint 21 embedded in the limiting groove of the lower die 12, and the pressure propagates along a straight line to the inner tube joint 21 and the lower die 12 with the ability of elastic deformation respectively. When the upper die 11 is pressed down to a certain extent, the inner tube joint 21 and the lower die 12 extend horizontally towards both ends with different deformation degrees respectively. When the pressure propagates along the embryo body of the inner tube joint 21 to the bottom position of the limiting groove, it pushes the tire embryo to continue to extend and deform along the depth direction of the limiting groove. At this time, the bottom of the limiting groove is not only affected by the first horizontal force generated by the deformation of the lower die 12, but also affected by the second horizontal force transmitted by the inner tube joint 21 along the horizontal direction. Under the dual action of the first horizontal force and the second horizontal force, its arc-shaped side surface begins to deform rapidly, and the bottom of its groove bottom is transmitted towards the impedance baffle 121 in clearance fit at the adjacent position. Under the continuous application of the external force, the inner tube joint 21 pushes the bottom of the limiting groove towards the impedance baffle 121 until it contacts the second part of the impedance baffle 121. The second part directly provided on the impedance baffle 121 vertically abuts against the bottom of the limiting groove and provides a supporting force against its extending direction to offset the pressure propagating along the horizontal direction, solving the problems of tire body deformation and joint dislocation caused by uneven force during the mating of the inner tube joint 21 with the flexible lower die 12, so as to improve the joint strength.

[0025] The above is only a preferred specific embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, making non-substantive modifications to the present invention using this concept, shall fall within the scope of infringement of the protection of the present invention.

Claims

1. An inner tube joint mold, comprising a lower die for supporting the inner tube joint, and an upper die for detachably pressing against the inner tube joint, characterized in that: The lower die is an elastic colloid die, and the bottom of the wall side thereof collapses inwards to form a limiting groove for embedding the inner tube joint; An impedance baffle is embedded in the side of the limiting groove away from the center direction of the lower die. When the inner tube joint arranged in the limiting groove has a radial deformation tendency under the pressure of the upper die, the impedance baffle supports the limiting groove and provides a force in the opposite direction of extension.

2. An inner tube joint mold according to claim 1, characterized in that: The impedance baffle includes a first portion extending along the width direction of the limiting groove, and a second portion extending along the depth direction of the limiting groove, and the first portion is rigidly connected to the second portion.

3. An inner tube joint mold according to claim 2, characterized in that: The impedance baffle is clearance-matched with the limiting groove.

4. An inner tube joint mold according to claim 2, characterized in that: The width of the limiting groove is twice the wall thickness of the inner tube joint.

5. The inner tube joint mold according to claim 2, characterized in that: The first part and the second part are made of metal material with predetermined rigidity, and the connection angle between the two is a right angle.

6. An inner tube joint mold according to claim 2, characterized in that: The rigid connection is welding.

7. The inner tube joint mold according to claim 1, characterized in that: The cross-sectional shape of the limiting groove is a semicircular arc, and the arc edge of the semicircular arc intersects tangentially with the bottom surface of the lower die.

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