Combined curing process for new energy automobile motor based on pre-curing

Abstract

The invention discloses a pre-curing-based combined curing process for a new energy automobile motor. Compared with an existing process, the process is divided into short-time pre-curing with a tool and long-time formal curing without the tool, and has remarkable characteristics. According to the process, short-time pre-curing and long-time formal curing are combined, the usage amount of tool clamps and the curing time are saved, the combination strength is improved, the problems existing in an existing process can be effectively solved, and the strict use requirement of a new energy automobile power control system is met.

Description

Technical Field

[0001] The invention relates to a combined curing process for a new energy automobile motor based on pre-curing. Background Art

[0002] With the development of the automobile industry, new energy vehicles have risen rapidly, the market has continued to expand, and the demand has increased. The quality and stability of the motor, the core functional component of new energy vehicles, plays a decisive role in the power control stability and driving safety of each new energy vehicle.

[0003] In the motor, the two core components, the housing and the magnetic tile, need to be effectively combined with epoxy resin glue to meet the requirement that the magnetic tile does not move when a thrust of 4000N is applied to the magnetic tile. Only in this way can the motor of new energy vehicles meet the use requirements, ensure that the magnetic tile does not fall off during high-speed driving, and the motor can operate normally and safely.

[0004] At present, there are two main processes for using epoxy resin glue: one is process A, which uses a high-frequency coil for rapid heating with a production cycle of 30 seconds; the other is process B, which is baked in an oven tunnel furnace, the motor parts are coated with glue and fixed on the positioning tooling, and the tooling and motor parts enter the oven tunnel furnace together for heating and curing and then cooling.

[0005] However, process A has obvious defects. Since the glue is heated up quickly by a high-frequency coil, it will cause the glue to suddenly expand and overflow the product, and gaps will appear in the glue, forming bubbles. As a result, the bonding force between the magnetic tiles in the motor and the casing does not meet the requirements, which may eventually cause the vehicle to lose balance and control due to the falling off of the magnetic tiles during driving, causing a major accident.

[0006] Although process B can ensure the stable quality of a single motor, the production cycle is relatively long. A single product needs to go through a process of heating up for 10 minutes, keeping the temperature constant for 10 minutes, and cooling down for 5 minutes, for a total of 25 minutes. In order to shorten the cycle to 15 seconds for mass production, 200 sets of clamping fixtures must be added to the tunnel furnace, which will greatly increase the cost of the automatic line. In addition, the use of 200 sets of fixtures for assembly will inevitably lead to poor repeatability and stability in the production and assembly of the motor, resulting in a defective rate of about 5%, making it impossible to fully guarantee the safety performance of mass-produced new energy vehicles. Summary of the invention

[0007] In order to solve the shortcomings of the existing technology, a more complete combined preparation process is now provided, which can effectively solve the problems existing in the existing process A or process B, thereby meeting the increasingly stringent use requirements of the power control system of new energy vehicles.

[0008] The specific plan is as follows:

[0009] A combined curing process for a new energy vehicle motor based on pre-curing, the process comprising the following steps:

[0010] S1. Apply glue to the surface of the magnetic tile to be bonded and bond it to the housing;

[0011] S2. Assemble the magnetic tile and the housing into a combined form, and achieve relative fixation in space through auxiliary tooling;

[0012] S3, at this time, the magnetic tile, the housing, and the auxiliary tooling are combined together and enter the pre-curing process;

[0013] S4, through segmented heating treatment, completing several heating and cooling processes to complete the pre-curing of the glue between the magnetic tile and the casing;

[0014] S5. After the auxiliary tooling is removed, the magnetic tile and the housing are in a pre-cured state and undergo a secondary curing process;

[0015] S6. Through heating treatment in multiple temperature control zones, the glue between the magnetic tile and the casing is formally cured;

[0016] S7. Cool and check the connection strength.

[0017] In order to improve the efficiency of pre-curing, the pre-curing in S4 includes the following steps:

[0018] S41, control the heating time to T11, so that the glue temperature reaches 95 + / - 10 ° C, and control the cooling time to T12, so that the glue temperature drops to 85 + / - 10 ° C;

[0019] S42, control the heating time to T21, so that the glue temperature reaches 160 + / - 10 ° C, and control the cooling time to T22, so that the glue temperature drops to 145 + / - 10 ° C;

[0020] S43, control the heating time to T31, the glue temperature reaches 210+ / -10℃, control the cooling time to T32, and reduce the glue temperature to 185+ / -10℃.

[0021] In order to highlight the effect of short-time pre-curing, thereby saving the use time of the tooling here and facilitating the circulation of the tooling, the heating time T11, T21, T31 and the cooling time T12, T22, T32 are all short times, with values ​​of 4-10s.

[0022] In order to improve the connection strength, the formal curing in S6 includes the following stages:

[0023] S61, heating stage, preheating the oven to a specified temperature, the magnetic tile and the housing enter the heating area on the conveyor belt in a pre-cured state, and after t1 time, the product temperature rises to the specified temperature;

[0024] S62, constant temperature stage, the oven temperature is kept constant at the specified temperature, and the product takes time t2 from entering to leaving the constant temperature section on the conveyor belt;

[0025] S63, cooling stage, cooling time is t3, cooling, the surface temperature of the product is ≤40℃.

[0026] When the applied glue is epoxy resin glue, the specified temperature in S6 is 180+ / -5°C.

[0027] Among them, t1, t2 and t3 are all long, with t1 being 8-12 minutes, t2 being more than 10 minutes, and t3 being 4-8 minutes.

[0028] Furthermore, after S4 is finished, the robot removes the product from the tooling, and after the CCD detects that the assembly size is qualified, it is placed on the tunnel furnace conveyor belt.

[0029] Beneficial effects:

[0030] By combining short-term pre-curing with long-term formal curing, the use of tooling and fixtures and curing time are saved, and the combined strength after preparation is also improved.

[0031] Referring to the usage mode of the original 200 sets of tooling on the automatic assembly line, the overall stability and CMK consistency of the 200 sets of tooling cannot be guaranteed. Among them, whether there is damage monitoring when the 200 sets of tooling are in use, whether a small number of tooling will be partially scrapped due to functional failure, the assembly line cannot achieve complete process control of the automatic line when producing motors.

[0032] To achieve the same production capacity, the new solution only requires three sets of tooling, which can be replicated more accurately. Since there are only three sets of tooling, the production process is stable and quality control is more convenient and effective. As a result, the motors produced are stable, the quality is controllable, the failure rate is reduced, and the end-users have a better driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a brief flow chart of this process. DETAILED DESCRIPTION

[0034] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0035] During motor assembly, the magnetic tile and the housing are bonded with epoxy resin glue. The curing of the glue must be done in an oven tunnel furnace to fully and effectively cure the glue. In order to eliminate the tooling that ensures the relative position and assembly size of the magnetic tile and the housing during curing in the oven tunnel furnace, before the glue is formally cured, the magnetic tile is glued and attached to the housing and the magnetic tile housing is fixed with tooling. A high-frequency coil is designed for heating pre-curing. The high-frequency heating coil is divided into 3 processes for sorting and execution:

[0036] The first coil power is 167KW. After heating for 6 seconds, the glue temperature reaches 95+ / -10℃. After cooling for 6 seconds, the glue temperature drops to 85+ / -10℃.

[0037] The second coil power is 175KW. After heating for 6 seconds, the glue temperature reaches 160+ / -10℃. After cooling for 6 seconds, the glue temperature drops to 145+ / -10℃.

[0038] The third section coil has a power of 190KW. After heating for 6 seconds, the glue temperature reaches 210+ / -10℃. After cooling for 6 seconds, the glue temperature drops to 185+ / -10℃. The robot removes the product from the tooling, and after the CCD detects that the assembly size is qualified, it is placed on the tunnel furnace conveyor belt.

[0039] After three stages of high-frequency coil heating, the epoxy resin glue is initially cured, and the edges of the glue at the joints between the magnetic tile and the casing have been cured, ensuring that the magnetic tile and the casing will not be relatively displaced or even slip when they are formally cured in the oven tunnel furnace. The cured epoxy resin glue only has edges, and the semi-finished assembly of the magnetic tile casing in this process (hereinafter referred to as "semi-finished product A") cannot meet the requirements of the drawings of "applying a 4000N thrust on the magnetic tile without the magnetic tile falling off", so it needs to be transferred to the oven tunnel furnace for formal curing. Tunnel furnace curing is divided into 3 stages:

[0040] In the first heating stage, the oven temperature is 180°C, and the semi-finished product A enters the tunnel oven on the conveyor belt. After 10 minutes, the temperature of the semi-finished product A rises to 180°C (the physical property table of epoxy resin glue requires a curing temperature of 180+ / -5°C and a curing time of 10 minutes);

[0041] In the second constant temperature stage, the oven temperature is kept constant at 180°C. The semi-finished product A takes ≥ 10 minutes from entering to leaving the constant temperature section on the conveyor belt.

[0042] The third cooling stage is natural air cooling, with an air intake fan at the bottom of the conveyor belt and an exhaust fan at the top of the conveyor belt. The wind speed is 5m / s and the air cooling time is 5 minutes. After 5 minutes, the surface temperature of semi-finished product A is ≤40℃.

[0043] Compared with the existing automatic assembly line with about 200 sets of tooling, this new process only requires 3 sets of tooling, reducing equipment costs; on the assembly line, 3-4 people were originally needed to clamp and unload 200 sets of tooling, and the new solution process reduces 3-4 operators.

[0044] It also improves the overall stability and CMK consistency, stabilizes the production process, and makes quality control more convenient and effective. The original solution uses high-frequency coil heating and curing, with a production cycle of 30 seconds; the original solution uses an oven tunnel furnace curing cycle that is approximately 15 seconds to 10 minutes, depending on the tooling and the length of the tunnel furnace; the new solution uses a process to produce an automatic motor assembly line, with a production assembly cycle of 13 seconds; it can greatly improve preparation efficiency and reduce costs.

[0045] As a further improvement, the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A combined curing process for new energy vehicle motors based on pre-curing, characterized in that: The process comprises the following steps: S1. Apply glue to the surface of the magnetic tile to be bonded and bond it to the housing; S2. Assemble the magnetic tile and the housing into a combined form, and achieve relative fixation in space through auxiliary tooling; S3, at this time, the magnetic tile, the housing, and the auxiliary tooling are combined together and enter the pre-curing process; S4, through segmented heating treatment, completing several heating and cooling processes to complete the pre-curing of the glue between the magnetic tile and the casing; S5. After the auxiliary tooling is removed, the magnetic tile and the housing are in a pre-cured state and undergo a secondary curing process; S6. Through heating treatment in multiple temperature control zones, the glue between the magnetic tile and the casing is formally cured; S7. Cool and check the connection strength.

2. A combined curing process for new energy vehicle motors based on pre-curing according to claim 1, characterized in that: The pre-curing in S4 includes the following steps: S41, control the heating time to T11, so that the glue temperature reaches 95 + / - 10 ° C, and control the cooling time to T12, so that the glue temperature drops to 85 + / - 10 ° C; S42, control the heating time to T21, so that the glue temperature reaches 160 + / - 10 ° C, and control the cooling time to T22, so that the glue temperature drops to 145 + / - 10 ° C; S43, control the heating time to T31, the glue temperature reaches 210+ / -10℃, control the cooling time to T32, and reduce the glue temperature to 185+ / -10℃.

3. A combined curing process for new energy vehicle motors based on pre-curing according to claim 2, characterized in that: in, The heating times T11, T21, T31 and the cooling times T12, T22, T32 are all short, with values ​​ranging from 4 to 10 seconds.

4. A combined curing process for new energy vehicle motors based on pre-curing according to claim 1, characterized in that: The formal solidification in S6 includes the following stages: S61, heating stage, preheating the oven to a specified temperature, the magnetic tile and the housing enter the heating area on the conveyor belt in a pre-cured state, and after t1 time, the product temperature rises to the specified temperature; S62, constant temperature stage, the oven temperature is kept constant at the specified temperature, and the product takes time t2 from entering to leaving the constant temperature section on the conveyor belt; S63, cooling stage, cooling time is t3, cooling, the surface temperature of the product is ≤40℃.

5. A combined curing process for new energy vehicle motors based on pre-curing according to claim 4, characterized in that: When the applied glue is epoxy glue, the specified temperature in S6 is 180+ / -5°C.

6. A combined curing process for new energy vehicle motors based on pre-curing according to claim 4 or 5, characterized in that: Among them, t1, t2 and t3 are all long, among which t1 is 8-12 minutes, t2 is more than 10 minutes, and t3 is 4-8 minutes.

7. A combined curing process for new energy vehicle motors based on pre-curing according to claim 2, 4 or 5, characterized in that: After S4 is finished, the robot removes the product from the tooling, and after the CCD detects that the assembly size is qualified, it is placed on the tunnel furnace conveyor belt.

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