An electromagnetic interference resistant end cover for automotive lock motors

Abstract

This utility model discloses an electromagnetic interference-resistant end cover for an automotive lock motor, comprising an end cover body, a thermal protector, a varistor, an inductor, a first carbon brush, a second carbon brush, a positive terminal, and a negative terminal. The first carbon brush is connected to one end of the thermal protector via a first conductive terminal, and the other end of the thermal protector is connected to the positive terminal. The second carbon brush is connected to one end of the inductor via a second conductive terminal, and the other end of the inductor is connected to the negative terminal. A first capacitor is connected between the first and second conductive terminals. The thermal protector of this utility model can automatically cut off the current when the motor is overloaded or the temperature is too high, preventing motor damage. The inductor can suppress electromagnetic interference, smoothing the current during frequent motor starts and stops and high-speed operation, thereby attenuating electromagnetic emission and radiation interference. The first and second capacitors filter out high-frequency noise and reduce current fluctuations, thereby effectively attenuating impedance-conducted interference. The overall structural layout is reasonable, effectively improving the electromagnetic compatibility and stability of the motor.

Description

Technical Field

[0001] This utility model relates to the field of motors, and in particular to an end cover for an automotive lock motor that is resistant to electromagnetic interference. Background Technology

[0002] With the widespread application of electronic control technology, automotive lock motors, as an actuator, are widely used in door locks, tailgate locks, and hood locks. However, since automotive locks are usually installed in door, tailgate, or hood areas, and these areas are surrounded by a large number of electronic control units (ECUs), sensors, wiring harnesses, and other electronic modules, a relatively complex electromagnetic environment is formed.

[0003] When the car lock motor is in operation, it generates strong electromagnetic interference due to its high-speed rotation, frequent start-stop and electromagnetic switching characteristics. In a complex electromagnetic environment, this interference can easily propagate through power supply lines, signal lines and grounding lines, thereby affecting the normal operation of other nearby electronic devices, causing the door control module to malfunction, signal distortion or even abnormalities in the whole vehicle control system.

[0004] In the prior art, in order to suppress the electromagnetic interference generated by the car lock motor, a shielding layer or a filter capacitor structure is usually added to the motor end cover. However, the attenuation and anti-interference effect is still poor in complex electromagnetic environments, which leads to control signal disorder or equipment malfunction, affecting the overall reliability of the vehicle.

[0005] Therefore, existing technologies have shortcomings and need to be improved. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide an automotive lock motor end cover with high stability and good anti-interference effect that can resist electromagnetic interference.

[0007] To achieve this objective, the present invention adopts the following technical solution: an electromagnetic interference resistant automotive lock motor end cover, comprising an end cover body, a thermal protector, a varistor, an inductor, a first carbon brush, a second carbon brush, a positive terminal, and a negative terminal;

[0008] The end cap body has a shaft hole in the middle, and the first carbon brush and the second carbon brush are located on both sides of the shaft hole for sliding contact with the commutator of the motor.

[0009] The end cap body is provided with a first receiving groove and a second receiving groove on both sides respectively. The thermal protector is located in the first receiving groove and the inductor is located in the second receiving groove.

[0010] The first carbon brush is connected to one end of the thermal protector via a first conductive terminal, and the other end of the thermal protector is connected to the positive terminal. The second carbon brush is connected to one end of the inductor via a second conductive terminal, and the other end of the inductor is connected to the negative terminal.

[0011] A circuit board is provided inside the end cap body above the shaft hole. The varistor is located on the top surface of the circuit board. One end of the varistor is connected to the positive terminal, and the other end of the varistor is connected to the negative terminal.

[0012] The above technical solution includes a first capacitor in the electromagnetic interference resistant car lock motor end cover. The first capacitor is located in the end cover body below the shaft hole and is connected between the first conductive terminal and the second conductive terminal.

[0013] The above-mentioned electromagnetic interference resistant car lock motor end cover also includes a second capacitor, which is located on the bottom surface of the circuit board and connected between the positive terminal and the negative terminal.

[0014] Using the above technical solution, in the electromagnetic interference resistant automotive lock motor end cover, the thermal protector is a PTC thermistor.

[0015] Using the above technical solution, in the electromagnetic interference resistant automotive lock motor end cover, the top surface of the circuit board is provided with a first copper foil layer and a second copper foil layer;

[0016] One end of the varistor is connected through the positive terminal of the first copper foil layer, and the other end of the varistor is connected through the negative terminal of the second copper foil layer.

[0017] Using the above technical solution, in the electromagnetic interference resistant automotive lock motor end cover, the back of the circuit board is provided with a third copper foil layer and a fourth copper foil layer;

[0018] One end of the second capacitor is connected to the positive terminal through a third copper foil layer, and the other end of the second capacitor is connected to the negative terminal through a fourth copper foil layer.

[0019] Using the above technical solution, in the electromagnetic interference resistant automotive lock motor end cover, the end cover body is provided with a support base, and the circuit board is disposed on the support base.

[0020] Using the above technical solution, in the electromagnetic interference resistant car lock motor end cover, the support base is provided with a third receiving groove, and the second capacitor is located in the third receiving groove.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The thermal protector of this invention can automatically cut off the current when the motor is overloaded or the temperature is too high, thus preventing motor damage; the inductor can suppress electromagnetic interference, smooth the current during frequent motor starts and stops and high-speed operation, and effectively attenuate electromagnetic emission radiation interference; the varistor can quickly respond to voltage fluctuations to absorb overvoltage and protect the motor and control system from damage; the first capacitor and the second capacitor can effectively filter out high-frequency noise, stabilize voltage, reduce current fluctuations, and prevent motor failure due to voltage fluctuations, thereby effectively attenuating impedance conduction interference; the overall structure layout is reasonable, effectively improving the electromagnetic compatibility and stability of the motor. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0025] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0026] Figure 2 This is a schematic diagram of the end cap body structure of this utility model;

[0027] Figure 3 This is a partial structural schematic diagram of the present invention;

[0028] Figure 4 This is a partial structural schematic diagram from another perspective of the present invention. Detailed Implementation

[0029] To make the utility model's objectives, features, and advantages more apparent and understandable, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0030] In the description of this utility model, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component centrally located at the same time.

[0031] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0032] like Figures 1 to 4 As shown, this utility model embodiment provides an electromagnetic interference resistant automotive lock motor end cover, including an end cover body 1, a thermal protector 2, a varistor 3, an inductor 4, a first carbon brush 51, a second carbon brush 52, a positive terminal 61, and a negative terminal 62. The end cover body 1 has a shaft hole 10 in the middle. The first carbon brush 51 and the second carbon brush 52 are respectively located on both sides of the shaft hole 10 for sliding contact with the commutator of the motor, so as to avoid current interruption or unstable motor operation due to poor contact.

[0033] The end cap body 1 has a first receiving groove 11 and a second receiving groove 12 on both sides. The thermal protector 2 is located in the first receiving groove 11, and the inductor 4 is located in the second receiving groove 12. The first carbon brush 51 is connected to one end of the thermal protector 2 through the first conductive terminal 71, and the other end of the thermal protector 2 is connected to the positive terminal 61. The second carbon brush 52 is connected to one end of the inductor 4 through the second conductive terminal 72, and the other end of the inductor 4 is connected to the negative terminal 62. The first carbon brush 51 is connected to one end of the thermal protector 2 through the first conductive terminal 71, and the other end of the thermal protector 2 is connected to the positive terminal 61. In this way, when the motor is overloaded or the temperature is too high, the thermal protector 2 can automatically cut off the current, thereby playing an overheat protection role and preventing the motor from being damaged by overcurrent or overheating. The inductor 4 can suppress electromagnetic interference when the motor is working, so that the current can be smoothed when the motor is frequently started and stopped and rotated at high speed, thereby effectively attenuating electromagnetic emission radiation interference and improving the stability of the car lock motor in long-term operation in complex working environments.

[0034] A circuit board 8 is provided inside the end cover body 1 above the shaft hole 10. The varistor 3 is located on the top surface of the circuit board 8. One end of the varistor 3 is connected to the positive terminal 61, and the other end of the varistor 3 is connected to the negative terminal 62. When the motor is working, when the commutator or other electrical components experience voltage changes or transient high voltage, the varistor 3 can quickly sense the voltage change and rapidly reduce its resistance, thereby effectively absorbing and dissipating overvoltage energy and preventing it from being conducted to the motor or control system, thus playing a protective role.

[0035] like Figure 1 and Figure 3 As shown, it further includes a first capacitor 91, which is disposed in the end cover body 1 below the shaft hole 10. The first capacitor 91 is connected between the first conductive terminal 71 and the second conductive terminal 72. The first capacitor 91 can filter out high-frequency noise and current spikes, reduce electromagnetic interference generated during motor operation, and improve the electromagnetic compatibility of the motor. At the same time, the capacitor also plays a role in stabilizing voltage and slowing down current fluctuations, so as to effectively attenuate impedance conduction interference.

[0036] like Figure 4As shown, it further includes a second capacitor 92, which is located on the bottom surface of the circuit board 8. The second capacitor 92 is connected between the positive terminal 61 and the negative terminal 62. The second capacitor 92 can provide an additional energy storage and release channel for the current when the motor is running, so as to absorb transient voltage spikes and high-frequency interference in the current and reduce the impact of electromagnetic interference on surrounding electronic equipment. The second capacitor 92 and the first capacitor 91 are equivalent to being connected in parallel in the circuit. Separating the two capacitors can reduce the internal resistance and increase the dissipation area, reduce the internal heat rise, and make the capacitor work more stably.

[0037] Furthermore, the thermal protector 2 is a PTC thermistor. PTC thermistors have a positive temperature coefficient and exhibit low resistance under normal operating temperature, allowing current to pass through normally. When the motor temperature rises due to overload or prolonged continuous operation during operation, the resistance of the PTC thermistor will increase rapidly, thereby limiting the current passing through and playing the role of current limiting and overheat protection.

[0038] like Figure 1 and Figure 3 As shown, the top surface of the circuit board 8 is provided with a first copper foil layer 81 and a second copper foil layer 82. One end of the varistor 3 is connected through the positive terminal 61 of the first copper foil layer 81, and the other end of the varistor 3 is connected through the negative terminal 62 of the second copper foil layer 82. In this way, a conductive path can be formed on the surface of the circuit board 8, so that the varistor 3 can be stably connected to the positive terminal 61 and the negative terminal 62.

[0039] like Figure 4 As shown, the back of the circuit board 8 is provided with a third copper foil layer 83 and a fourth copper foil layer 84. One end of the second capacitor 92 is connected to the positive terminal 61 through the third copper foil layer 83, and the other end of the second capacitor 92 is connected to the negative terminal 62 through the fourth copper foil layer 84.

[0040] like Figure 2 As shown, further, the end cap body 1 is provided with a support base 13, the circuit board 8 is disposed on the support base 13, the support base 13 is provided with a third receiving groove 14, and the second capacitor 92 is located in the third receiving groove 14. In this way, the installation structure stability of the second capacitor 92 can be improved, and loosening due to motor vibration can be prevented.

[0041] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An electromagnetic interference resistant end cover for an automotive lock motor, characterized in that, It includes the end cap body, thermal protector, varistor, inductor, first carbon brush, second carbon brush, positive terminal and negative terminal; The end cap body has a shaft hole in the middle, and the first carbon brush and the second carbon brush are located on both sides of the shaft hole for sliding contact with the commutator of the motor. The end cap body is provided with a first receiving groove and a second receiving groove on both sides respectively. The thermal protector is located in the first receiving groove and the inductor is located in the second receiving groove. The first carbon brush is connected to one end of the thermal protector via a first conductive terminal, and the other end of the thermal protector is connected to the positive terminal. The second carbon brush is connected to one end of the inductor via a second conductive terminal, and the other end of the inductor is connected to the negative terminal. A circuit board is provided inside the end cap body above the shaft hole. The varistor is located on the top surface of the circuit board. One end of the varistor is connected to the positive terminal, and the other end of the varistor is connected to the negative terminal.

2. The electromagnetic interference resistant automotive lock motor end cover according to claim 1, characterized in that, It also includes a first capacitor, which is disposed in the end cap body below the shaft hole and is connected between the first conductive terminal and the second conductive terminal.

3. The electromagnetic interference resistant automotive lock motor end cover according to claim 1, characterized in that, It also includes a second capacitor, which is located on the bottom surface of the circuit board and is connected between the positive terminal and the negative terminal.

4. The electromagnetic interference resistant automotive lock motor end cover according to claim 1, characterized in that, The thermal protector is a PTC thermistor.

5. The electromagnetic interference resistant automotive lock motor end cover according to claim 1, characterized in that, The top surface of the circuit board is provided with a first copper foil layer and a second copper foil layer; One end of the varistor is connected through the positive terminal of the first copper foil layer, and the other end of the varistor is connected through the negative terminal of the second copper foil layer.

6. The electromagnetic interference resistant automotive lock motor end cover according to claim 3, characterized in that, The back of the circuit board is provided with a third copper foil layer and a fourth copper foil layer; One end of the second capacitor is connected to the positive terminal through a third copper foil layer, and the other end of the second capacitor is connected to the negative terminal through a fourth copper foil layer.

7. The electromagnetic interference resistant automotive lock motor end cover according to claim 3, characterized in that, The end cap body is provided with a support base, and the circuit board is disposed on the support base.

8. The electromagnetic interference resistant automotive lock motor end cover according to claim 7, characterized in that, The support base is provided with a third receiving slot, and the second capacitor is located in the third receiving slot.

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