A method for controlling overflow of adhesive at the bonded end face of a carbon fiber friction cone ring of a synchronizer

Abstract

The application discloses a synchronous carbon fiber friction cone ring adhesive end face glue overflow control method, which realizes glue overflow control by controlling the performance index of thermosetting phenolic resin, controlling the weaving pore of pre-impregnated carbon fiber cloth, controlling the glue content and controlling the volatile content. The application effectively solves the problems of adhesive glue overflow from the end face of the cone ring and interface unqualification in the production process of the friction ring, improves the production efficiency and product qualification rate of the cone ring, improves the cleanliness of the hot-pressing clamp, prolongs the service life of the clamp, reduces the cleaning and maintenance frequency of the clamp and use cost. In the case that the adhesive glue cannot be changed, by controlling various indexes of the pre-impregnated carbon fiber cloth and comprehensively applying various means, the glue overflow and interface unqualification phenomenon in the hot-pressing and shaping process of the synchronous carbon fiber friction cone ring are effectively solved, so that the pre-impregnated carbon fiber cloth meets the application requirements of the hot-pressing and shaping rapid curing process.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of automobile transmission technology, and relates to a synchronous carbon fiber friction cone ring, in particular to a synchronous carbon fiber friction cone ring adhesive end face overflow control method. BACKGROUND

[0002] The synchronous carbon fiber friction cone ring uses carbon fiber cloth impregnated with resin as friction material and is produced by adopting a hot-pressing setting rapid curing process. During hot-pressing setting, the cone ring is rapidly heated from room temperature to about 160℃ in about 4 minutes, and the adhesive film is rapidly changed from solid state to liquid state with good fluidity. Affected by many factors, such as Figure 1 and Figure 2 As can be seen from the comparison, the liquid adhesive is prone to a large number of micro-bubbles and overflow from the end face of the cone ring, resulting in adhesive loss, incomplete filling of the adhesive layer of the adhesive interface, generation of adhesive interface line pattern or point-like adhesive defects, and unqualified adhesive quality. The overflow of the adhesive from the end face will cause the hot-pressing clamp to be stained with adhesive particles, reducing the cleanliness of the clamp. In order to ensure the quality and size requirements of the cone ring, the clamp needs to be cleaned frequently during production, increasing labor intensity and reducing production efficiency. SUMMARY

[0003] In view of the deficiencies in the prior art, the purpose of the present application is to provide a synchronous carbon fiber friction cone ring adhesive end face overflow control method to solve the technical problem that the production efficiency and product qualification rate of the synchronous carbon fiber friction cone ring are to be further improved due to overflow of the adhesive from the adhesive end face of the cone ring in the prior art.

[0004] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0005] A synchronous carbon fiber friction cone ring adhesive end face overflow control method, which realizes overflow control by controlling the performance indicators of the thermosetting phenolic resin of the pre-impregnated carbon fiber cloth, controlling the weaving porosity of the pre-impregnated carbon fiber cloth, controlling the adhesive content, and controlling the volatile content.

[0006] The present application also has the following technical features:

[0007] The method for controlling the performance indicators of the thermosetting phenolic resin is to use a thermosetting phenolic resin with a number average molecular weight of not less than 600 as the pre-impregnated resin for preparing the carbon fiber friction material.

[0008] The method for controlling the weaving porosity of the pre-impregnated carbon fiber cloth is to use the butyl nitrile rubber in the pre-impregnated resin solution of the carbon fiber cloth in an amount of not less than 15wt%.

[0009] The method for controlling the adhesive content is to control the adhesive content of the pre-impregnated carbon fiber cloth to be not more than 19.2g per 30cm 2 The total weight of the pre-impregnated carbon fiber cloth containing adhesive is not more than 19.2g.

[0010] The method for controlling the volatile content is that the volatile content of the pre-impregnated carbon fiber cloth after drying is less than or equal to 0.8 wt.%.

[0011] The method further comprises controlling the surface cleanliness of the pre-impregnated carbon fiber cloth.

[0012] The method for controlling the surface cleanliness of the pre-impregnated carbon fiber cloth is that there is no glue liquid accumulation on the surface of the pre-impregnated carbon fiber cloth.

[0013] Compared with the prior art, the present application has the following technical effects:

[0014] (I) The present application first discovers that the performance indicators of the thermosetting phenolic resin of the pre-impregnated carbon fiber cloth, the weaving porosity of the pre-impregnated carbon fiber cloth, the glue content, the volatile content, and the surface cleanliness are all influencing factors of the overflow of glue and the unqualified interface in the production and hot pressing of the synchronizer carbon fiber friction cone ring.

[0015] (II) The present application effectively solves the problems of overflow of adhesive glue from the end face of the cone ring and unqualified interface in the production process of the friction ring, improves the production efficiency and product qualification rate of the cone ring, improves the cleanliness of the hot pressing clamp, prolongs the service life of the clamp, and reduces the cleaning and maintenance frequency and use cost of the clamp.

[0016] (III) In the case that the adhesive glue cannot be changed, by controlling the various indicators of the pre-impregnated carbon fiber cloth and comprehensively applying various means, the present application effectively solves the overflow of glue and the unqualified interface in the hot pressing and setting process of the synchronizer carbon fiber friction cone ring, so that the pre-impregnated carbon fiber cloth meets the application requirements of the hot pressing and setting rapid curing process.

[0017] (IV) The present application clearly identifies the reason for the overflow of glue from the end face during the hot pressing of the synchronizer cone ring.

[0018] (V) The present application discovers the selection requirements of the phenolic resin of the pre-impregnated carbon fiber cloth suitable for the hot pressing and setting rapid curing process, the quality requirements of the pre-impregnated carbon fiber cloth, and the control method of the weaving porosity of the pre-impregnated carbon fiber cloth. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The figure is a photo of a synchronizer carbon fiber friction cone ring without overflow of glue, uniform glue ring without bubbles, and qualified interface.

[0020] Figure 2 The figure is a photo of a synchronizer carbon fiber friction cone ring with much overflow of glue and bubbles, and unqualified interface.

[0021] Figure 3 The figure is a photo of a pre-impregnated carbon fiber cloth with small porosity after impregnation and drying.

[0022] Figure 4Photo of the well-maintained pores after impregnation and drying

[0023] Figure 5 Photo of the surface of the prepreg carbon fiber cloth with the glue accumulated.

[0024] Figure 6 Photo of the surface of the prepreg carbon fiber cloth with the glue accumulated.

[0025] Figure 7 Photo of the heat-pressing and shaping of the cone ring in the clamp.

[0026] The specific content of the present application is further explained in detail in the following combined with examples. DETAILED DESCRIPTION

[0027] It should be noted that all the equipment and materials in the present application, if not specifically stated, are all known equipment and materials in the prior art.

[0028] The following gives specific examples of the present application, it should be noted that the present application is not limited to the following specific examples, any equivalent transformation made on the basis of the technical solutions of the present application falls within the protection scope of the present application.

[0029] Example:

[0030] The present example gives a method for controlling the overflow of the adhesive on the end face of the carbon fiber friction cone ring of the synchronizer, which realizes the overflow control by controlling the performance index of the thermosetting phenolic resin of the prepreg carbon fiber cloth, controlling the weaving porosity of the prepreg carbon fiber cloth, controlling the glue content and controlling the volatile content.

[0031] Specifically, the method for controlling the performance index of the thermosetting phenolic resin is: using a thermosetting phenolic resin with a number average molecular weight not less than 600 as the prepreg resin for the preparation of the carbon fiber friction material; in the present example, the cone ring of the synchronizer uses the carbon fiber cloth impregnated with the resin as the friction material, and the carbon fiber cloth is prepreged with the thermosetting phenolic resin as the main body. The thermosetting phenolic resin is the primary influencing factor for whether the overflow phenomenon occurs in the heat-pressing and shaping process; selecting a thermosetting phenolic resin with a number average molecular weight not less than 600 as the prepreg resin for the preparation of the carbon fiber friction material can greatly avoid the occurrence of overflow and other unqualified phenomena in the heat-pressing and shaping process. Further, the content of free small molecules in the thermosetting phenolic resin is as low as possible.

[0032] Specifically, the method for controlling the weaving porosity of the pre-impregnated carbon fiber cloth is that the amount of nitrile rubber in the pre-impregnated resin solution of the carbon fiber cloth is not less than 15wt%; in this embodiment, a small amount of epoxy resin and nitrile rubber is added to the pre-impregnated resin solution of the carbon fiber cloth in a physical mixing or polymerization manner, so as to adjust the viscosity of the pre-impregnated resin solution of the carbon fiber cloth at different temperature sections, make the carbon fiber directional, positioning bonding, and also improve the bonding performance, wear resistance, impact resistance and processability of the friction material; if the amount of nitrile rubber is less, as shown in FIG. 8, the weaving porosity of the pre-impregnated carbon fiber cloth after drying becomes small, which is not conducive to the overflow of residual small molecules; if the amount of nitrile rubber is not less than 15wt%, the weaving porosity of the pre-impregnated carbon fiber cloth before and after pre-impregnation can be kept good, as shown in FIG. 9, and an escape channel is left for the residual small molecules in the pre-impregnated carbon fiber cloth during the hot-pressing and shaping process, so as to avoid the overflow of small molecules from the bonding interface and cause bonding defects. Figure 3 Figure 4

[0033] Specifically, the method for controlling the glue content is that the total weight of the pre-impregnated carbon fiber cloth containing bonding glue is not higher than 19.2g. In this embodiment, the higher the glue content, the more likely the glue overflow phenomenon occurs, and the glue content of the pre-impregnated carbon fiber cloth needs to be controlled within a certain range. When the glue content of the pre-impregnated carbon fiber cloth is not higher than 19.2g, it can be ensured that the friction material has good friction performance, and the end face glue overflow phenomenon during the hot-pressing and shaping stage can be prevented. 2

[0034] Specifically, the method for controlling the volatile content is that the volatile content of the pre-impregnated carbon fiber cloth after drying is less than or equal to 0.8wt.%; in this embodiment, in order to prevent the end face glue overflow during the hot-pressing and shaping stage, the volatile content of the pre-impregnated carbon fiber cloth after drying is as low as possible, and is generally controlled within 0.8wt.%.

[0035] As a preferred scheme of this embodiment, the method further includes controlling the surface cleanliness of the pre-impregnated carbon fiber cloth; the method for controlling the surface cleanliness of the pre-impregnated carbon fiber cloth is that there is no glue liquid accumulation on the surface of the pre-impregnated carbon fiber cloth. In this embodiment, the poor appearance of the pre-impregnated carbon fiber cloth, as shown in FIG. 10, can also cause the end face glue overflow during the hot-pressing. The surface of the pre-impregnated carbon fiber cloth must be kept clean, as shown in FIG. 11, and glue liquid accumulation and other phenomena cannot occur, so as to avoid the escape channel of small molecules being blocked. Figure 5 Figure 6

[0036] The process of the synchronizer carbon fiber friction cone ring bonding friction material in this embodiment includes the following steps:

[0037] Step one, preparing a pre-impregnated resin solution;

[0038] Step two, immersing the carbon fiber cloth in the pre-impregnated resin solution at a set speed, and then controlling the resin content and appearance quality through a scraper or a metering roller; ​​​​​

[0039] Step three, after the carbon fiber cloth is immersed in the resin solution, it is dried by an oven to volatilize the solvent, and then is wound up;

[0040] Step four, the resin content, thickness and porosity of the pre-impregnated carbon fiber cloth are detected, and the carbon fiber cloth is used after being qualified.

[0041] Step five, after the pre-impregnated carbon fiber cloth is cut into strips, the strips are bonded and laminated with the cone ring base;

[0042] Step six, the bonded cone ring is loaded into a hot-pressing clamp, preheated, and then taken out after being kept at pressure for 7-9 min, and the end face rubber ring and the appearance quality of the cone ring are checked; Figure 7

[0043] Step seven, post-curing is performed by stage heating, and then the part is taken out after being cooled down, and the curing production of the carbon fiber friction cone ring of the synchronizer is completed.​

Claims

1. A method for controlling glue overflow on the bonding end face of a synchronizer carbon fiber friction cone ring, characterized in that: The method realizes glue overflow control by controlling the thermosetting phenolic resin performance index of the pre-impregnated carbon fiber cloth, controlling the weaving pores of the pre-impregnated carbon fiber cloth, controlling the glue content and controlling the volatile matter content; The method for controlling the performance index of the thermosetting phenolic resin is as follows: using a thermosetting phenolic resin with a number average molecular weight of not less than 600 as a prepreg resin when preparing the carbon fiber friction material; The method for controlling the woven pores of the pre-impregnated carbon fiber cloth is as follows: the amount of nitrile rubber in the pre-impregnated resin solution of the carbon fiber cloth is not less than 15wt%; The method for controlling the glue content is: every 30cm 2 The total weight of the pre-impregnated carbon fiber cloth containing pre-impregnated resin shall not exceed 19.2g; The method for controlling the volatile matter content is as follows: the volatile matter content of the pre-impregnated carbon fiber cloth is less than or equal to 0.8 wt.% after drying.

2. The method for controlling glue overflow on the bonding end face of the synchronizer carbon fiber friction cone ring according to claim 1, characterized in that: The method also includes controlling the surface cleanliness of the prepreg carbon fiber cloth.

3. The method for controlling glue overflow on the bonding end face of the synchronizer carbon fiber friction cone ring according to claim 2, characterized in that: The method for controlling the surface cleanliness of the prepreg carbon fiber cloth is as follows: no glue is accumulated on the surface of the prepreg carbon fiber cloth.

Images