CN102941662B - Multi-cavity compound rubber strip extruding mold - Google Patents

Abstract

The invention discloses a multi-cavity compound rubber strip extruding mold which comprises a pressing ring, a mandril fixing piece, a main material molding piece, a mandril, a dowel pin, a compound molding piece and a mold. The pressing ring, the mandril fixing piece, the main material molding piece, the compound molding piece and the mold are arranged horizontally and sequentially. The mandril and the dowel pin penetrate through the pressing ring, the mandril fixing piece, the main material molding piece, the compound molding piece and the mold. The multi-cavity compound rubber strip extruding mold further comprises a plurality of main runners and an auxiliary material sprue. The auxiliary material sprue is arranged on a central axis of the mold, the main runners are distributed according to 360-degree array average angles, cavity runner structures of the main runners are uniform, and distances between the main runners and the auxiliary material sprue are equal. Compared with a single-cavity compound mold, under the same extruding pressure, resistance for the rubber fluid passing through the mold is small, extruding speed is high, production efficiency is greatly improved, and manufacture process cost is saved. Extruded molded multi-cavity compound rubber strips are even in walls and good in product size uniformity.

Description

A multi-cavity composite rubber strip extrusion die

technical field

The invention relates to the technical field of rubber extrusion molding, in particular to a multi-cavity composite rubber strip extrusion die. the

Background technique

At present, the mold structure for the production of composite rubber strips adopts the method of feeding and extruding materials in the vertical direction of two rubber extrusion molding machines. The main machine extrudes one rubber material (rubber material with more materials), and the auxiliary machine extrudes the other. material (rubber material with a small amount). Adjust the pressure of the main machine and auxiliary machine to control the extrusion speed and the wall thickness of the auxiliary material layer. The heating ring and thermocouple are used to control the die temperature, and the cooling water circulation controls the temperature of the rubber fluid in the uncompounded state.

However, the existing mold structure has the following deficiencies:

1. The single-cavity composite mold can only extrude one composite rubber strip at a time, which is inefficient. However, when the existing multi-cavity composite mold is used to extrude multiple composite rubber strips, the pressure cannot be controlled uniformly, resulting in product defects;

2. The flow channel of the auxiliary material (also known as auxiliary material glue) is perpendicular to the flow channel of the main material, and when mixed with the main material, the auxiliary material will squeeze the main material under the action of its own gravity, resulting in deformation;

3. When the extruding pressure of the auxiliary material is too high, there will be glue leakage between the mandrel fixing part and the main material forming part;

4. Because only one end of the mandrel is fixed (through the mandrel fixing part), it is easy to shake under the action of the rubber fluid (that is, the main material and the auxiliary material are mixed), and there will be traces on the surface of the extruded composite rubber strip, and the composite rubber The round hole of the bar will also appear eccentric.

In view of this, the prior art needs to be improved and improved. the

Contents of the invention

In view of the deficiencies in the prior art, the purpose of the present invention is to provide a multi-cavity composite rubber strip extrusion die. The invention aims to solve the problems of glue leakage, poor quality of molded products and the like existing in molds for producing composite rubber strips in the prior art.

Technical scheme of the present invention is as follows:

A multi-cavity composite rubber strip extrusion die, comprising: a pressure ring, a mandrel fixing part, a main material molding, a mandrel, a positioning pin, a composite molding and a die; the pressure ring, the mandrel fixing part, the main The material molded part, the composite molded part and the die are arranged horizontally in sequence, and the mandrel and the positioning pin run through the pressure ring, the mandrel fixing part, the main material molded part, the composite molded part and the die; wherein, the multi-cavity composite rubber The strip extrusion die also includes several main channels and an auxiliary material gate, the auxiliary material gate is arranged on the central axis of the mold, the main channels are distributed according to the average angle of 360-degree array, and the cavity flow channel structure of each main channel is consistent, And the distance from the auxiliary material gate is equal;

The auxiliary material glue enters the auxiliary flow channel through the auxiliary material port set on the side of the mandrel fixing part, and enters the main flow channel through the auxiliary material gate, and is compounded with the main material glue, coated on the surface of the main material glue, and then heated and vulcanized from the die Medium extrusion molding.

Preferably, in the multi-cavity composite rubber strip extrusion die, a constricted inclined step is provided in the auxiliary runner.

Preferably, in the multi-cavity composite rubber strip extrusion die, the auxiliary runner includes corners for buffering.

Preferably, in the multi-cavity composite rubber strip extrusion die, the angle of the corner is 90 degrees.

Preferably, the multi-cavity composite rubber strip extrusion die also includes a runner set for avoiding excessive extrusion pressure of auxiliary materials and leakage of glue, and the runner set connects the mandrel fixing part and the main material moldings.

Preferably, the multi-cavity composite rubber strip extrusion die further includes a mandrel support for supporting the mandrel, and the mandrel support is arranged between the composite molding and the die.

Preferably, in the multi-cavity composite rubber strip extrusion die, the mandrel support is a mandrel support with a single-side support structure.

Preferably, in the multi-cavity composite rubber strip extrusion die, the width of the support structure on one side is 0.3mm.

Preferably, in the multi-cavity composite rubber strip extrusion die, there are five main channels, and the angle between adjacent main channels and the center of the circle is 72 degrees.

Preferably, in the multi-cavity composite rubber strip extrusion die, there are eight main channels, and the angle between adjacent main channels and the center of the circle is 45 degrees.

Beneficial effect:

The multi-cavity composite rubber strip extrusion die of the present application is compared with the single-cavity composite die at the same extrusion pressure, the resistance of the rubber fluid passing through the die will be smaller, and the extrusion speed will be faster, adding the multi-cavity die The output quantity is more, which greatly improves the production efficiency and saves the cost of the manufacturing process; at the same time, it ensures that the extruded multi-cavity composite rubber strip has uniform wall thickness and good product size consistency.

Description of drawings

Fig. 1 is an exploded schematic diagram of an embodiment of a multi-cavity composite rubber strip extrusion die of the present application.

Fig. 2 is a schematic cross-sectional view of the main material molding in the embodiment of the multi-cavity composite rubber strip extrusion die of the present application.

Fig. 3 is a schematic cross-sectional view of the main material molding in another embodiment of the multi-cavity composite rubber strip extrusion die of the present application.

Fig. 4 is a schematic cross-sectional view of the auxiliary runner in the embodiment of the multi-cavity composite rubber strip extrusion die of the present application.

Fig. 5 is a schematic cross-sectional view of the mandrel support in the embodiment of the multi-cavity composite rubber strip extrusion die of the present application.

Detailed ways

The present invention provides a multi-cavity composite rubber strip extrusion die. In order to make the purpose, technical solution and effect of the present invention clearer and clearer, the present invention will be further described in detail below. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Please refer to FIG. 1 , which is an exploded schematic diagram of an embodiment of a multi-cavity composite rubber strip extrusion die of the present application. As shown in the figure, the multi-cavity composite rubber strip extrusion die includes: pressure ring 100, mandrel fixing part 200, main material molding part 300, mandrel 400, positioning pin 500, composite molding part 600 and die 700; The pressure ring 100, the mandrel fixing part 200, the main material molding part 300, the composite molding part 600 and the die 700 are arranged horizontally in sequence, and the mandrel 400 and the positioning pin 500 run through the pressure ring 100, the mandrel fixing part 200, Main material molding 300 , composite molding 600 and die 700 .

Please refer to Figure 1 and Figure 2 together, the multi-cavity composite rubber strip extrusion die also includes several main channels 800 and an auxiliary material gate 900, the auxiliary material gate 900 is arranged on the central axis of the mould, the main channel The 800 is distributed according to the average angle of the 360-degree array, and the cavity flow channel structure of each main channel 800 is consistent, and the distance from the auxiliary material gate 900 is equal. In this embodiment, the number of the main channels 800 is five, and the angle a between adjacent main channels and the center of the circle is 72 degrees.

Specifically, the auxiliary material glue enters the auxiliary flow channel through the auxiliary material port (not shown in the figure) provided on the side of the mandrel fixing part 200, and enters the main flow channel 800 through the auxiliary material gate 900, and is compounded with the main material glue. Cover the surface of the main rubber, and then extrude from the die 700 through heating and vulcanization. By designing the auxiliary material gate on the central axis of the mold, the main channel is designed at the same distance around the auxiliary gate, the number of cavities is distributed according to the average angle of the 360° array, and the structure and distance of the runners of each cavity are exactly the same. In this way, the distance between the auxiliary material gate and each main channel is equal, which ensures that the force between each main channel and auxiliary material gate is equal, so that the consistency of the product is better. The number of cavities can be determined according to the size of the mold and the actual application status of the product. As shown in Figure 3, an 8-cavity mold can also be used (that is, the number of sprue 800 is 8), and the gap between the adjacent sprue and the center of the circle Angle b is 45 degrees.

Further, as shown in FIG. 4 , a constricted inclined step portion 110 is provided in the auxiliary flow channel to achieve the balance of the auxiliary material glue flowing therein. In addition, the secondary channel also includes a corner portion 120 for buffering. In this embodiment, the angle of the corner 120 is 90 degrees, and the auxiliary material glue (entered from the b1 port) releases a certain pressure through the 90° corner flow channel, and is squeezed when it is compounded with the main rubber flow channel The degree is very small, it only needs to be coated on the surface of the main rubber (entering from b2 port), and the final shaped product is extruded from b3 port.

Furthermore, as shown in Figure 1, the multi-cavity composite rubber strip extrusion die also includes a runner set 130 for avoiding excessive extruding pressure of auxiliary materials to cause glue leakage, and the runner set 130 is connected to the core Rod fixing part 200 and main material molding part.

In order to prevent the mandrel from shaking under the action of flow force, the multi-cavity composite rubber strip extrusion die also includes a mandrel support 140 for supporting the mandrel, as shown in Figure 1, the mandrel support 140 It is arranged between the composite molding 600 and the die 700 . In this way, one end of the mandrel is fixed on the mandrel holder, and the other end is supported by the mandrel bracket 140 , so that the round hole of the formed product will not be eccentric.

Further, in order to prevent traces on the surface of the extruded composite rubber strip (caused by the mandrel support frame), in this embodiment, a single support (about 0.3mm wide) is used in the direction of the auxiliary material feeding. Mandrel support 140, as shown in FIG. 5 . After many tests, it was found that the extrusion force on the mandrel mainly acts on the direction in which the auxiliary material enters the glue, so it only needs to be supported in a single direction. In this way, the surface of the extruded composite rubber strip will hardly Traces appear, guaranteeing the performance and appearance of the product.

After trial production, it is found that the advantage of this mold is that when the multi-cavity composite rubber strip extrusion mold is compared with the single-cavity composite mold at the same extrusion pressure, the resistance of the rubber fluid passing through the mold will be smaller, and the extrusion speed will be faster. In addition, the output of the multi-cavity mold itself is larger, which greatly improves the production efficiency and saves the cost of the manufacturing process. At present, there have been cases of 5-cavity composite extrusion molds. The production efficiency is 5 times that of single-cavity molds, and the extrusion production cost is only 20% of that of single-cavity molds. And it can also be adapted to extrude composite rubber strip products with two different rubber materials, such as conductive and non-conductive, different hardness, different colors, translucent and opaque, foamed and non-foamed.

In summary, the multi-cavity composite rubber strip extrusion die of the present invention includes: a press ring, a mandrel fixing part, a main material molding, a mandrel, a positioning pin, a composite molding and a die; the press ring, The mandrel fixing part, the main material forming part, the composite forming part and the die are arranged horizontally in sequence, and the mandrel and the positioning pin run through the pressure ring, the mandrel fixing part, the main material forming part, the composite forming part and the die; wherein, The multi-cavity composite rubber strip extrusion die also includes several main channels and an auxiliary material gate, the auxiliary material gate is arranged on the central axis of the mould, the main channels are distributed according to the average angle of the 360-degree array, and each main channel The structure of the cavity flow channel is the same, and the distance from the auxiliary material gate is equal; the auxiliary material glue enters the auxiliary flow channel through the auxiliary material port set on the side of the mandrel fixing part, and enters the main flow channel through the auxiliary material gate, and is compounded with the main material glue. Cover the surface of the main rubber, and then extrude from the die through heating and vulcanization. Compared with the single-cavity composite mold at the same extrusion pressure, the resistance of the rubber fluid passing through the mold will be smaller, and the extrusion speed will be faster. In addition, the output of the multi-cavity mold itself is more, greatly improving It improves production efficiency and saves manufacturing process costs; at the same time, it ensures that the extruded multi-cavity composite rubber strip has uniform wall thickness and good product size consistency.

It should be understood that the application of the present invention is not limited to the above examples, and those skilled in the art can make improvements or changes based on the above descriptions, such as changing the number of cavities, the angle of the corners, etc. All these improvements and changes are Should belong to the scope of protection of the appended claims of the present invention.

Claims (7)

1. A multi-cavity composite rubber strip extrusion die, comprising: pressure ring, mandrel fixing part, main material molding, mandrel, positioning pin, composite molding and die; said pressure ring, mandrel fixing part , the main material molding, the composite molding and the die are arranged horizontally in sequence, and the mandrel and the positioning pin run through the pressure ring, the mandrel fixing part, the main material molding, the composite molding and the die; it is characterized in that the The multi-cavity composite rubber strip extrusion die also includes several main channels and an auxiliary material gate, the auxiliary material gate is arranged on the central axis of the mould, the main channels are distributed according to the average angle of the 360-degree array, and the cavity flow of each main channel The channel structure is consistent, and the distance from the auxiliary material gate is equal; The auxiliary material glue enters the auxiliary flow channel through the auxiliary material port set on the side of the mandrel fixing part, and enters the main flow channel through the auxiliary material gate, and is compounded with the main material glue, coated on the surface of the main material glue, and then heated and vulcanized from the die middle extrusion molding; A constricted inclined step is arranged in the auxiliary flow channel; The auxiliary flow channel includes corners for buffering; It also includes a flow channel set for avoiding glue leakage due to excessive extrusion pressure of the auxiliary material, and the flow channel set connects the mandrel fixing part and the main material molding part. 2. The multi-cavity composite rubber strip extrusion die according to claim 1, wherein the angle of the corner is 90 degrees. 3. multi-cavity composite rubber strip extrusion die according to claim 1, is characterized in that, also comprises a mandrel support for supporting mandrel, and described mandrel support is arranged between composite molding and die . 4. The multi-cavity composite rubber strip extrusion die according to claim 3, wherein the mandrel support is a mandrel support with a single-side support structure. 5. The multi-cavity composite rubber strip extrusion die according to claim 4, characterized in that the width of the single-side support structure is 0.3mm. 6. The multi-cavity composite rubber strip extrusion die according to claim 1, wherein the number of said main channels is five, and the angle between adjacent main channels and the center of the circle is 72 degrees. 7. The multi-cavity composite rubber strip extrusion die according to claim 1, wherein the number of said main channels is 8, and the angle between adjacent main channels and the center of a circle is 45 degrees.