Method for manufacturing a rubber coupling

Abstract

The application discloses a rubber coupling preparation method and belongs to the rubber field. The rubber coupling preparation method comprises the following steps: defining the space between the inner surface of the sleeve and the outer surface of the mold core as an overflow space, and the flow separator needs to be capable of closing the overflow space and the mold cavity; adding a heat-resistant agent and a tackifier into raw rubber to obtain a to-be-processed flow separator rubber compound; injecting the to-be-processed flow separator rubber compound into a flow separator mold, and performing vulcanization forming to obtain a flow separator; performing grinding treatment on the surface of the flow separator; sequentially arranging a first sleeve, the flow separator and a second sleeve on the mold core; and after vulcanization is completed, the flow separator is integrated with the raw rubber. The flow separator can block the raw rubber and the overflow space, so that the raw rubber is only vulcanized and molded in the mold cavity, the mold core is facilitated to be separated from the rubber coupling after molding, a process of removing the excess rubber in the later stage is saved, and the product quality of the rubber coupling is ensured.

Description

Technical Field

[0001] This application relates to the field of rubber, and more specifically, to a method for preparing a rubber coupling. Background Technology

[0002] A rubber coupling consists of two sleeves bonded together with rubber after vulcanization. The rubber coupling allows bolts to pass through the sleeves, connecting the driving and driven ends.

[0003] For example, Chinese patent document (CN103589158B) provides a material and method for preparing rubber couplings, which involves placing a dried coupling skeleton (i.e., sleeve) into a mold for fixation and performing vulcanization treatment according to the injection molding vulcanization process to obtain the finished rubber coupling.

[0004] During this process, because rubber is semi-fluid during vulcanization, it is very easy to drill rubber into the inner hole of the coupling frame. After the rubber material in the inner hole of the sleeve is formed, it greatly increases the difficulty of demolding. In order to ensure product quality, it also takes a certain amount of time to clean the rubber in the inner hole of the frame. The defect rate of rubber couplings is also greatly increased.

[0005] Therefore, how to improve the drilling of rubber into the inner hole of rubber couplings during the vulcanization molding process and improve product quality is an urgent problem to be solved in the industrial production of rubber couplings. Summary of the Invention

[0006] The main objective of this application is to provide a method for manufacturing a rubber coupling to solve the problem of drilling rubber into the inner hole of the rubber coupling.

[0007] To achieve the above objectives, according to one aspect of this application, a method for manufacturing a rubber coupling is provided. The rubber coupling to be processed includes a first sleeve, a second sleeve, and raw rubber material. The method includes the following steps:

[0008] Step 1: Define the space between the inner surface of the sleeve and the outer surface of the mold core as the overflow space. The flow divider must be able to seal the overflow space from the mold cavity. Construct the flow divider mold according to this requirement.

[0009] Step 2: Add heat-resistant agent and tackifier to the original rubber compound to obtain the rubber compound for the flow barrier to be processed; inject the rubber compound for the flow barrier to be processed into the flow barrier mold and vulcanize it to obtain the flow barrier; grind the surface of the flow barrier.

[0010] Step 3: Install the first sleeve, the flow divider, and the second sleeve onto the mold core in sequence; inject the raw rubber material into the rubber coupling mold and vulcanize it; after vulcanization, the flow divider and the raw rubber material become one piece;

[0011] Step 4: Open the mold and remove the rubber coupling.

[0012] Furthermore, in step two, after grinding the surface of the flow divider, the flow divider is fitted onto the through rod, and adhesive is sprayed onto the outer surface of the flow divider. The diameter of the through rod is equal to the inner diameter of the flow divider. After the adhesive is sprayed, the flow divider is removed from the processing rod.

[0013] Furthermore, in step two, the adhesive thickness on the surface of the flow barrier is 0.01 mm to 0.02 mm.

[0014] Furthermore, in step two, the vulcanization degree of the flow barrier is 80% to 100% of the vulcanization degree of the original rubber compound in step three.

[0015] Furthermore, in step one, the flow-blocking component is constructed as a rotating body structure with the central axis as the axis of rotation; the inner diameter of the flow-blocking component is equal to the inner diameter of the rubber coupling, and the axial distance of the flow-blocking component is greater than the axial distance between the first sleeve and the second sleeve of the rubber coupling.

[0016] Furthermore, the rubber coupling mold includes an upper mold and a lower mold. When the upper mold and the lower mold are closed, multiple mold cavities are formed for batch vulcanizing of rubber couplings.

[0017] Furthermore, in step three, after the first sleeve, the flow divider, and the second sleeve are sequentially installed on the mold core, a limiting component is installed to prevent the rubber coupling from shifting laterally during the vulcanization process.

[0018] Furthermore, an injection groove is formed on the side of the upper mold opposite to the mold cavity, and an injection hole is provided at the bottom of the injection groove, which leads to multiple mold cavities; an injection device is provided above the mold, and the injection device has an injection protrusion that can be embedded in the injection groove.

[0019] Furthermore, in step three, after the limiting component is installed onto the mold core, the mold core is placed into the mold cavity. After the mold is closed, the original rubber material is filled into the injection groove. The injection device presses into the injection groove, and the original rubber material enters the mold cavity from the injection hole. When the original rubber material flows to the flow barrier, it accumulates in the direction away from the mold core until the gap in the mold cavity is filled.

[0020] Furthermore, two opposing mounting grooves are provided on the inner surface of the limiting component, and a limiting mechanism that can extend into the mold core is fixed in the groove; the mold core is correspondingly formed with a groove to accommodate one end of the limiting mechanism; the upper mold and the lower mold are correspondingly provided with limiting grooves to hold the limiting component.

[0021] Furthermore, the limiting mechanism includes a spring and a telescopic rod, with the telescopic rod fixedly connected to the spring. The spring is fixed to the bottom of the mounting groove, and the end of the telescopic rod away from the spring is hemispherical.

[0022] Further, step four specifically involves: opening the mold, and after opening the mold, removing the limiting component, the mold core, and the rubber coupling together; removing the limiting component from the mold core, and pulling the mold core out of the rubber coupling.

[0023] The benefits of this application are:

[0024] The space between the inner surface of the sleeve and the outer surface of the mold core is defined as the overflow space. The flow divider needs to be able to seal the overflow space from the mold cavity. The flow divider mold is constructed according to this requirement. The flow divider can isolate the original rubber material from the overflow space, so that the original rubber material is vulcanized and shaped only in the mold cavity. This facilitates the removal of the mold core from the molded rubber coupling and eliminates the need for the later process of removing excess rubber, thus ensuring the product quality of the rubber coupling.

[0025] The vulcanization degree of the baffle is 80% to 100% of the original rubber compound's vulcanization degree. Here, the vulcanization degree refers to the degree of cross-linking achieved between rubber macromolecules under specific temperature and time conditions. Within this range, the baffle, after subsequent secondary vulcanization, will not become brittle and fragile due to excessive vulcanization, nor will it deform easily, causing rubber compound to flow into the overflow space, due to insufficient vulcanization. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings:

[0027] Figure 1 This is a cross-sectional view of a rubber coupling according to an embodiment of this application;

[0028] Figure 2 This is a cross-sectional structural diagram of a rubber coupling mold according to an embodiment of this application;

[0029] Figure 3 This is a general flowchart of the rubber coupling manufacturing method involved in this application;

[0030] Figure label:

[0031] 100. Rubber coupling; 110. First sleeve; 120. Second sleeve;

[0032] 200. Rubber coupling mold; 210. Upper mold; 211. Injection groove; 220. Lower mold; 230. Mold cavity; 240. Groove; 250. Injection hole; 260. Mold core; 261. Limiting protrusion;

[0033] 300. Limiting component; 310. Mounting slot; 320. Limiting mechanism; 321. Spring; 322. Telescopic rod;

[0034] 400, flow barrier; 500, injection device; 510, injection protrusion. Detailed Implementation

[0035] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0036] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances.

[0037] This embodiment relates to a method for preparing a rubber coupling, used to prepare a rubber coupling 100, referring to... Figure 1 As shown, the rubber coupling 100 to be processed includes a first sleeve 110, a second sleeve 120, and raw rubber material. This application does not impose specific limitations on the composition of the raw rubber material; it can be any material suitable for producing the rubber coupling 100.

[0038] The method for manufacturing this rubber coupling includes the following steps, the general process of which is as follows: Figure 3 As shown:

[0039] Step 1: Define the space between the inner surface of the sleeve and the outer surface of the mold core 260 as the overflow space. The flow divider 400 must be able to close the overflow space and the connection between the overflow space and the mold cavity 230. Construct the flow divider mold according to this requirement.

[0040] Step 2: Add heat-resistant agent and tackifier to the original rubber compound to obtain the rubber compound for the flow barrier to be processed; inject the rubber compound for the flow barrier to be processed into the flow barrier mold and vulcanize it to obtain the flow barrier 400; grind the surface of the flow barrier 400.

[0041] Step 3: Install the first sleeve, the flow divider, and the second sleeve onto the mold core in sequence; inject the raw rubber material into the rubber coupling mold 200 and vulcanize it; after vulcanization, the flow divider 400 and the raw rubber material become one.

[0042] Step 4: Open the mold and remove the rubber coupling 100.

[0043] During the manufacturing process, a rubber coupling mold 200 is used to vulcanize and plasticize the rubber coupling 100 to be processed. The rubber coupling mold 200 includes an upper mold 210, a lower mold 220, a mold core 260, a limiting component 300, and an injection device 500. In order to improve production efficiency, the upper mold 210 and the lower mold 220 can form multiple mold cavities 230 when they are closed, which are used for batch vulcanizing of the rubber coupling 100.

[0044] The limiting member 300 is used to prevent the rubber coupling 100 from shifting laterally during vulcanization. The inner surface of the limiting member 300 has two opposing mounting grooves 310, in which a limiting mechanism 320 extending towards the mold core 260 is fixed. The mold core 260 has a corresponding groove 240 to accommodate one end of the limiting mechanism 320. The upper mold 210 and lower mold 220 are respectively provided with limiting grooves to hold the limiting member 300 in place. Specifically, the limiting mechanism 320 includes a spring 321 and a telescopic rod 322. The telescopic rod 322 is fixedly connected to the spring 321, which is fixed to the bottom of the mounting groove 310. The end of the telescopic rod 322 away from the spring 321 is hemispherical. More specifically, the mold core 260 also has a limiting protrusion 261 to engage with the limiting groove.

[0045] A pressure injection groove 211 is formed on the side of the upper mold 210 opposite to the mold cavity 230. A glue injection hole 250 is provided at the bottom of the pressure injection groove 211, leading to multiple mold cavities 230. A pressure injection device 500 is provided above the mold, and the pressure injection device 500 has a pressure injection protrusion 510 that can be embedded into the pressure injection groove 211. When the pressure injection protrusion 510 is pressed into the pressure injection groove 211, the raw rubber material can simultaneously enter all mold cavities 230 of the rubber coupling mold 200 through the glue injection hole 250.

[0046] The rubber coupling manufacturing method of this embodiment specifically includes the following steps:

[0047] Step 1: Define the space between the inner surface of the sleeve and the outer surface of the mold core 260 as the overflow space. The flow divider 400 must be able to seal the connection between the overflow space and the mold cavity 230. Construct the flow divider 400 mold according to this requirement. In related technologies, due to the fluid properties of the raw rubber material, it will always seep into the overflow space. After subsequent high-temperature vulcanization, the raw rubber material, after molding, adheres to the inner hole of the sleeve, causing product quality issues. Therefore, to solve this problem, the flow divider 400 is used to isolate the raw rubber material from the overflow space, so that the raw rubber material is vulcanized and molded only in the mold cavity 230. The flow divider 400 mold involved in this step can be reused repeatedly in the subsequent preparation of the flow divider 400.

[0048] Specifically, the dimensions of the flow divider 400 are determined based on the dimensions of the rubber coupling 100 to be produced. The flow divider 400 is constructed as a rotating body structure with its central axis as the axis of rotation. The inner diameter of the flow divider 400 is equal to the inner diameter of the rubber coupling 100, that is, the inner diameter of the flow divider 400 is equal to the inner diameter of the sleeve, and also equal to the outer diameter of the mold core 260. Due to manufacturing process and assembly requirements, a certain degree of error is allowed between the inner diameter of the flow divider 400, the inner diameter of the rubber coupling 100, the inner diameter of the sleeve, and the outer diameter of the mold core 260. This error does not affect the preparation of the rubber coupling 100. The axial distance between the flow-blocking component 400 and the first sleeve 110 and the second sleeve 120 of the rubber coupling 100 is greater than the axial distance between them. This "greater than" ensures an interference fit between the flow-blocking component 400 and the first and second frames in the axial direction, preventing gaps between the flow-blocking component 400 and the sleeves that could lead to leakage of the original rubber material. This does not actually affect the assembly steps of the flow-blocking component 400 in subsequent manufacturing processes. More specifically, the outer diameter of the flow-blocking component 400 should not be greater than or equal to the outer diameter of the sleeve, ensuring a stepped fit between the final vulcanized original rubber material thickness and the frame, thus guaranteeing the working strength of the rubber coupling 100.

[0049] Step 2: Add heat-resistant agent and tackifier to the original rubber compound to obtain the rubber compound of the flow barrier 400 to be processed; inject the rubber compound of the flow barrier 400 to be processed into the mold of the flow barrier 400 and perform vulcanization molding to obtain the flow barrier 400; grind the surface of the flow barrier 400.

[0050] Since the flow divider 400 needs to undergo high-temperature vulcanization again in subsequent steps to become part of the rubber coupling 100, the rubber compound of the flow divider 400 needs to have better heat resistance in order to reduce the negative impact of repeated vulcanization on the final performance of the rubber coupling 100. Simultaneously, to ensure a tight bond between the flow divider 400 and the original rubber compound, the viscosity and adhesion of the flow divider 400 rubber compound need to be improved. To achieve these objectives, heat-resistant agents and tackifiers need to be added to the original rubber compound. Otherwise, even if the risk of rubber adhering to the inner hole of the sleeve is avoided, the product may still fail due to insufficient strength of the final flow divider 400 or an unstable connection between the flow divider 400 and the original rubber compound. Specifically, the tackifier used in this step is C6 petroleum tackifier resin, used in amounts of 5-8 parts.

[0051] Specifically, the vulcanization degree of the baffle 400 is 80% to 100% of the original rubber compound's vulcanization degree. Here, vulcanization degree refers to the degree of cross-linking achieved between rubber macromolecules under specific temperature and time conditions. Within this range, the baffle 400, after subsequent secondary vulcanization, will not become brittle and fragile due to excessive vulcanization, nor will it deform easily and fail to effectively prevent the rubber compound from flowing into the overflow space due to insufficient vulcanization.

[0052] After the baffle 400 is vulcanized and molded, its surface often has release agent or other free additives, which hinders the subsequent bonding with the original rubber compound. In this step, after demolding, the baffle 400 needs to be ground. As an optional solution, the baffle 400 can be ground using a finishing machine. Pebbles and water are added to the rotating part of the finishing machine, and then the baffle 400 is inserted for grinding.

[0053] Furthermore, in step two, to ensure a stronger bond between the baffle 400 and the original adhesive, the first skeleton, and the second skeleton, after grinding the surface of the baffle 400, it is fitted onto the through rod, and adhesive is sprayed onto the outer surface of the baffle 400. Specifically, multiple baffles 400 can be connected in series simultaneously on the through rod, with the diameter of the through rod equal to the inner diameter of the baffle 400. This avoids adhesive being sprayed onto the inner surface of the baffle 400 during the spraying process. As an optional option, Chemitac 80 adhesive is used, and the baffle 400 is processed using a universal spray gun with a nozzle diameter of 0.3mm to 0.6mm. More specifically, the thickness of the adhesive on the outer surface of the baffle 400 is 0.01mm to 0.02mm. If the adhesive thickness is less than 0.01mm, it is easy to cause uneven spraying, fewer adhesive molecules per unit surface area, and low strength. If it is greater than 0.02mm, it is easy to produce bubbles, defects and premature fracture. Moreover, the expansion stress after heating is large, which can easily lead to joint damage and thus bonding failure.

[0054] After the adhesive is applied, remove the baffle 400 from the processing rod for later use.

[0055] Step 3: After installing the first sleeve 110, the flow divider 400, and the second sleeve 120 into the mold core 260 in sequence, install the limiting member 300 into the mold core 260, place the mold core 260 into the mold cavity 230, and after the mold is closed, fill the injection groove 211 with rubber material. The injection device 500 presses into the injection groove 211, and the rubber material enters the mold cavity 230 from the injection hole 250. When the rubber material flows to the flow divider 400, it accumulates in the direction away from the mold core 260 until the gap in the mold cavity 230 is filled. After high-temperature heating, the rubber coupling 100 is vulcanized and formed. After vulcanization, the flow divider 400 and the original rubber material become one.

[0056] Step 4: Open the mold. After opening the mold, remove the limiting part 300, the mold core 260 and the rubber coupling 100 together. Remove the limiting part 300 from the mold core 260 and pull the mold core 260 out of the rubber coupling 100.

[0057] During the vulcanization molding of the rubber coupling 100 of this application, the limiting member 300 and the mold core 260 in the rubber coupling mold 200 are synchronously and tightly fitted with the upper mold 210 and the lower mold 220. The flow-blocking member 400 generates lateral extrusion force due to thermal expansion between the first sleeve 110 and the second sleeve 120, so that the first sleeve 110 and the second sleeve 120 are respectively tightly abutted against the limiting member 300 and the limiting protrusion 261 of the mold core 260. This prevents the rubber material from entering the inner hole of the sleeve from multiple directions, which not only facilitates the removal of the mold core 260 from the molded rubber coupling 100, but also eliminates the need for the later process of removing excess rubber, thus ensuring the product quality of the rubber coupling 100.

[0058] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate for the embodiments of this application described herein.

[0059] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0060] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for manufacturing a rubber coupling, used to manufacture a rubber coupling, wherein the rubber coupling to be processed includes a first sleeve, a second sleeve, and raw rubber material; characterized in that: The rubber coupling mold includes an upper mold and a lower mold. When the upper mold and the lower mold are closed, they form multiple mold cavities for batch vulcanizing rubber couplings. An injection groove is formed on the side of the upper mold opposite to the mold cavity. An injection hole is provided at the bottom of the injection groove, and the injection hole leads to multiple mold cavities. An injection device is provided above the mold, and the injection device has an injection protrusion that can be embedded into the injection groove; The method for manufacturing the rubber coupling includes the following steps: Step 1: Define the space between the inner surface of the sleeve and the outer surface of the mold core as the overflow space. Construct a flow-blocking mold. The flow-blocking component must be able to seal the overflow space from the mold cavity. The flow-blocking component is a rotating body structure with the central axis as the axis of rotation. The inner diameter of the flow-blocking component is equal to the inner diameter of the rubber coupling. The axial distance of the flow-blocking component is greater than the axial distance between the first and second sleeves of the rubber coupling. Step 2: Add heat-resistant agent and tackifier to the original rubber compound to obtain the rubber compound for the flow barrier to be processed; inject the rubber compound for the flow barrier to be processed into the flow barrier mold and vulcanize it to obtain the flow barrier; grind the surface of the flow barrier. Step 3: Install the first sleeve, the flow divider, and the second sleeve onto the mold core in sequence; after installing the first sleeve, the flow divider, and the second sleeve onto the mold core in sequence, install the limiting component to prevent the rubber coupling from shifting laterally during the vulcanization process; After the limiting component is installed onto the mold core, the mold core is placed into the mold cavity. After the mold is closed, the original rubber material is filled into the injection groove. The injection device presses into the injection groove, and the original rubber material enters the mold cavity from the injection hole. When the original rubber material flows to the flow divider, it accumulates away from the mold core until the gap in the mold cavity is filled. The original rubber material is then injected into the rubber coupling mold for vulcanization. After vulcanization, the flow barrier and the original rubber compound become one. Step 4: Open the mold and remove the rubber coupling.

2. The method for preparing a rubber coupling according to claim 1, characterized in that: In step two, after grinding the surface of the flow divider, the flow divider is fitted onto the through rod, and adhesive is sprayed onto the outer surface of the flow divider. The diameter of the through rod is equal to the inner diameter of the flow divider. After the adhesive is sprayed, the flow divider is removed from the processing rod.

3. The method for preparing a rubber coupling according to claim 2, characterized in that: In step two, the adhesive thickness on the surface of the flow barrier is 0.01 mm to 0.02 mm.

4. The method for manufacturing a rubber coupling according to claim 1, characterized in that: In step two, the degree of vulcanization of the flow barrier is 80% to 100% of the degree of vulcanization of the original rubber compound in step three.

5. The method for manufacturing a rubber coupling according to claim 1, characterized in that: Two opposing mounting grooves are provided on the inner surface of the limiting component, and a limiting mechanism that can extend into the mold core is fixed in the groove; the mold core is correspondingly formed with a groove to accommodate one end of the limiting mechanism; The upper and lower molds are respectively provided with limit grooves to lock the limit components.

6. The method for manufacturing a rubber coupling according to claim 5, characterized in that: The limiting mechanism includes a spring and a telescopic rod. The telescopic rod is fixedly connected to the spring, and the spring is fixed to the bottom of the mounting groove. The end of the telescopic rod away from the spring is hemispherical.

7. The method for manufacturing a rubber coupling according to claim 6, characterized in that: Step four specifically involves: opening the mold, removing the limiting component, mold core, and rubber coupling together after opening the mold; removing the limiting component from the mold core and pulling the mold core out of the rubber coupling.

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