Multifunctional mutual induction electric window anti-pinch controller and control method

Abstract

The present invention discloses a multifunctional mutual-inductance electric window anti-pinch controller and a control method, wherein the multifunctional mutual-inductance electric window anti-pinch controller comprises a control circuit and an armature BEM signal mutual inductor T1, the control circuit comprises a main control chip U1, and the armature BEM signal mutual inductor T1 comprises a primary winding and a secondary winding; one end of the primary winding and one end of the secondary winding are grounded at the same time, the other end of the primary winding is used to access the BEM ripple signal, and the other end of the secondary winding is electrically connected to one end of the main control chip U1; the present invention samples the BEM ripple signal of a window motor M when it rotates through the armature BEM signal mutual inductor T1, and the main control chip U1 monitors the pulse width change of the motor BEM signal, thereby accurately judging whether the electric window clamps an object during the rising process, and timely controlling the window motor M when encountering an obstacle to prevent the object or human body from being clamped, thereby realizing the window anti-pinch function.

Description

Technical Field

[0001] The invention relates to the technical field of motor control, and in particular to a multifunctional mutual-inductance electric window anti-pinch controller and a control method. Background Art

[0002] With the advancement of modern automotive electronic technology, traditional parts and assemblies in automobiles are also developing towards mechatronics. Among them, the extensive application of electronic equipment in automobiles is conducive to improving the comfort and convenience of automobiles, but some electronic equipment has certain safety risks during use. As people's requirements for safety are getting higher and higher, how to ensure the comfort and simplicity of automobiles while improving the safety performance of electronic equipment in automobiles has also become a trend in the current development of automobiles.

[0003] In the prior art, a large number of cars use electric windows for the convenience of drivers and passengers, but many electric windows do not have all the following functions in one: glass anti-pinch function, one-button window closing function, one-button window opening function, automatic window closing function when parking, etc. In particular, the anti-pinch function is more likely to cause harm to passengers, especially children. Therefore, for the sake of safety, it is absolutely necessary to develop a multifunctional window anti-pinch control module. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a multifunctional mutual-inductance electric window anti-pinch controller and a control method to realize the window anti-pinch function.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A multifunctional mutual inductance electric window anti-pinch controller, comprising a control circuit and an armature BEM signal mutual inductor T1, wherein the control circuit comprises a main control chip U1, and the armature BEM signal mutual inductor T1 comprises a primary winding and a secondary winding;

[0007] One end of the primary winding and one end of the secondary winding are grounded at the same time, the other end of the primary winding is used to access the BEM ripple signal, and the other end of the secondary winding is electrically connected to one end of the main control chip U1;

[0008] The main control chip U1 is used to generate an anti-pinch control signal capable of controlling the operation of the window motor M according to the pulse width deformation of the BEM ripple signal.

[0009] In order to solve the above technical problems, another technical solution adopted by the present invention is:

[0010] The mutual induction electric window anti-pinch control method comprises the following steps:

[0011] S1, collecting the BEM ripple signal of the window motor M;

[0012] S2. Determine whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold. If so, generate an anti-pinch control signal to control the operation of the window motor M.

[0013] The beneficial effects of the present invention are: a multifunctional mutual-inductance electric window anti-pinch controller and control method, which samples the BEM ripple signal of the window motor M during rotation through the armature BEM signal mutual inductor T1, and the main control chip U1 monitors the pulse width change of the motor BEM signal, thereby accurately judging whether the electric window clamps an object during the rising process, and when encountering an obstacle, timely controlling the window motor M to prevent objects or human bodies from being pinched, thereby realizing the window anti-pinch function. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A circuit diagram of a multifunctional mutual-inductance electric window anti-pinch controller according to an embodiment of the present invention;

[0015] Figure 2 It is a structural schematic diagram of an armature BEM signal transformer involved in an embodiment of the present invention;

[0016] Figure 3 It is a structural schematic diagram of the anti-pinch area involved in an embodiment of the present invention;

[0017] Figures 4 to 6 Schematic diagrams of the ECU module and the vehicle window in different implementations of the embodiments of the present invention;

[0018] Figure 7 A schematic diagram of a flow chart of a mutual-sensing electric window anti-pinch control method according to an embodiment of the present invention;

[0019] Figure 8 The figure is a schematic diagram of a specific process of a mutual-inductance electric window anti-pinch control method according to an embodiment of the present invention.

[0020] Description of labels:

[0021] T1, armature BEM signal transformer; U1, main control chip; U2, operational amplifier; U3, three-terminal power supply voltage regulator chip; U4, driver chip; U5, Schmitt trigger; D1, diode; M, window motor; K1, relay; R1-R17, resistors; C1-C8 and C12-C16, capacitors. DETAILED DESCRIPTION

[0022] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0023] Please refer to Figures 1 to 8, a multifunctional mutual inductance electric window anti-pinch controller, comprising a control circuit and an armature BEM signal mutual inductor T1, wherein the control circuit comprises a main control chip U1, and the armature BEM signal mutual inductor T1 comprises a primary winding and a secondary winding;

[0024] One end of the primary winding and one end of the secondary winding are grounded at the same time, the other end of the primary winding is used to access the BEM ripple signal, and the other end of the secondary winding is electrically connected to one end of the main control chip U1;

[0025] The main control chip U1 is used to generate an anti-pinch control signal capable of controlling the operation of the window motor M according to the pulse width deformation of the BEM ripple signal.

[0026] From the above description, it can be seen that the beneficial effects of the present invention are: the BEM ripple signal of the window motor M is sampled by the armature BEM signal transformer T1 when it is rotating, and the pulse width change of the motor BEM signal is monitored by the main control chip U1, so as to accurately judge whether the electric window clamps an object during the rising process, and when encountering an obstacle, the window motor M is controlled in time to prevent objects or human bodies from being clamped, thereby realizing the anti-pinch function of the window.

[0027] Furthermore, the control circuit also includes an operational amplifier U2, a Schmitt trigger U5 and a driving chip U4;

[0028] The other end of the secondary winding is electrically connected to the sixth pin of the operational amplifier U2, the seventh pin of the operational amplifier U2 is electrically connected to the first pin of the Schmitt trigger U5 after passing through an RC filter circuit, and the twelfth pin of the Schmitt trigger U5 is electrically connected to the second pin of the main control chip U1;

[0029] The tenth pin of the main control chip U1 is electrically connected to the first pin of the driving chip U4, the eleventh pin of the main control chip U1 is electrically connected to the second and third pins of the driving chip U4, and the seventh and eighth pins of the driving chip U4 generate a driving signal that can drive the relay K1 to control the operation of the window motor M.

[0030] Among them, the BEM ripple signal is collected by the armature BEM signal transformer T1 and amplified by the operational amplifier U2, and then converted into a digital pulse signal after passing through the Schmitt trigger U5. Therefore, the main control chip U1 processes the pulse width change of the digital pulse signal converted from the BEM ripple signal.

[0031] From the above description, it can be seen that the operational amplifier U2 is used to amplify the signal, and the Schmitt trigger U5 converts the analog signal into a digital pulse signal, which is provided to the main control chip U1 to determine whether an obstacle is encountered. When an obstacle is encountered, the corresponding switch signal is output to the driver chip U4, and then the output of the corresponding channel of the driver chip U4 is used to drive the relay K1 to control the reverse rotation of the window motor M, so that the window is lowered to prevent objects or human bodies from being pinched, thereby realizing the window anti-pinch function.

[0032] Furthermore, a resistor R13 is included, one end of the resistor R13 is electrically connected to one end of the primary winding and the other end of the resistor R13 is electrically connected to the fourteenth pin of the main control chip U1.

[0033] From the above description, it can be seen that a resistor R13 is connected to one end of the primary winding to detect the change of the motor armature current, and the change of the motor armature current is sent to the main control chip U1 to implement overcurrent protection when the motor is stalled.

[0034] Further, it also includes a capacitor C12, a resistor R15 and a capacitor C6;

[0035] One end of the capacitor C12 is connected to the input voltage signal and the other end is electrically connected to the second pin of the operational amplifier U2, one end of the resistor R15 and one end of the capacitor C6. The other end of the resistor R15 and the other end of the capacitor C6 are electrically connected to the first pin of the operational amplifier U2. The first pin of the operational amplifier U2 is electrically connected to the eighteenth pin of the main control chip U1.

[0036] From the above description, it can be seen that the ripple signal of the motor operation is collected by the capacitor C12, and the signal is amplified by the resistor R15, the capacitor C6 and the internal unit of the operational amplifier U2, and then output to the main control chip U1 through the first pin of the operational amplifier U2 to realize the automatic window closing function when parking.

[0037] Furthermore, the primary winding includes a primary magnetic ring and a constantan wire wound around the primary magnetic ring for 1-2 turns, the constantan wire has a diameter of 1.5 mm and a resistance of 5-10 milliohms, and the secondary winding includes a secondary magnetic ring and an enameled wire wound around the secondary magnetic ring for 500-1000 turns, the diameter of the enameled wire is 0.1 mm.

[0038] From the above description, it can be seen that the ratio of the primary coil to the secondary coil of the armature BEM signal transformer T1 is 1:500. When the window motor M is rotating, the BEM ripple signal is sampled by the transformer T1 and increased to a sufficient voltage amplitude (1:500), and then connected to the sixth pin of the operational amplifier U2 for amplification.

[0039] Furthermore, it also includes a voltage stabilizing circuit, which includes a three-terminal power supply voltage stabilizing chip U3, a diode D1, a capacitor C7 and a capacitor C8;

[0040] The anode of the diode D1 is connected to the input voltage signal and the cathode is electrically connected to the first pin of the three-terminal power supply voltage regulator chip U3 and one end of the capacitor C7. The third pin of the three-terminal power supply voltage regulator chip U3 is electrically connected to the first pin of the main control chip U1, the eighth pin of the operational amplifier U2, the fourteenth pin of the Schmitt trigger U5 and one end of the capacitor C8. The second pin of the three-terminal power supply voltage regulator chip U3, the other end of the capacitor C7 and the other end of the capacitor C8 are grounded.

[0041] Furthermore, the input voltage signal is 12V, and the output voltage signal of the third pin of the three-terminal power supply voltage regulator chip U3 is 5V.

[0042] From the above description, it can be seen that the three-terminal power supply regulator chip U3 regulates the 12V input voltage into a 5V output voltage to supply power to the main control chip U1, the operational amplifier U2 and the Schmitt trigger U5 for normal operation.

[0043] Please refer to Figures 1 to 8 , a mutual induction electric window anti-pinch control method, comprising the steps of:

[0044] S1, collecting the BEM ripple signal of the window motor M;

[0045] S2. Determine whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold. If so, generate an anti-pinch control signal to control the operation of the window motor M.

[0046] From the above description, it can be seen that the beneficial effects of the present invention are: the BEM ripple signal of the window motor M is sampled by the armature BEM signal transformer T1 when it is rotating, and the pulse width change of the motor BEM signal is monitored by the main control chip U1, so as to accurately judge whether the electric window clamps an object during the rising process, and when encountering an obstacle, the window motor M is controlled in time to prevent objects or human bodies from being clamped, thereby realizing the anti-pinch function of the window.

[0047] Furthermore, the step S2 specifically includes the following steps:

[0048] Determine whether the time after the window motor M is started reaches the preset delay time. If so, determine whether the pulse width deformation of the BEM ripple signal is greater than the preset threshold. If so, generate an anti-pinch control signal to control the operation of the window motor M. The preset delay time is between 40ms and 60ms.

[0049] From the above description, it can be seen that when the window motor M is just started, the back electromotive force of the motor has not yet been established, so the current will have a short-term large amplitude. The current amplitude at this time is often larger than the set overcurrent protection current threshold. It is necessary to distinguish this state of large current amplitude from encountering obstacles during the window rising process. Therefore, after the window motor M is started, an appropriate delay is performed before the BEM ripple signal is detected, which can avoid the impact of the instantaneous overshoot at the initial stage of the motor starting on the overcurrent threshold setting and the anti-pinch threshold setting.

[0050] Furthermore, the step S2 specifically includes the following steps:

[0051] Read the current position of the window and the key input signal. If the key input signal is a window lifting signal, output a switch signal to drive the window motor M to move up and down. If the window lifting signal is a window rising signal, count up the BEM pulse signal to obtain the real-time position of the window. If the window lifting signal is a window falling signal, count down the BEM pulse signal to obtain the real-time position of the window. The BEM pulse signal is a digital pulse signal obtained after the Schmitt trigger U5 converts the BEM ripple signal.

[0052] Determine whether the real-time position of the window is in the anti-pinch area. If so, determine whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold. If so, generate an anti-pinch control signal to control the reverse of the window motor M. The anti-pinch area is between the lowest value of the window rise and the highest value of the window rise. The lowest value of the window rise ranges from 30 mm to 80 mm when the window rises from the bottom, and the highest value of the window rise ranges from 3 mm to 5 mm when the window rises from the top.

[0053] From the above description, it can be seen that the rotation of the window motor M will drive the movement of the wire rope, thereby controlling the up and down movement of the window. During the movement of the window, the number of turns of the motor is proportional to the movement distance of the window, and the rotation of the motor rotor will cause the mutual inductor to sense a pulse signal. When the window rises from the lowest position to the top, the pulse signal output by the armature BEM signal mutual inductor T1 can be counted by the main control chip U1 and recorded in the memory. Afterwards, the software controls the window to start running from the bottom position, and the window runs to the top and the motor stops, and the counting starts from zero. The rising process is counted according to the current count value, and the falling process is counted according to the current count value. Therefore, the pulse output and counting scheme of the armature BEM signal mutual inductor T1 can be used to determine the current position of the window in real time, and whether the anti-pinch function of the window is enabled can be determined according to the anti-pinch area determined above.

[0054] Please refer to Figures 1 to 8 , Embodiment 1 of the present invention is:

[0055] A multifunctional mutual inductance electric window anti-pinch controller includes a control circuit, a voltage stabilizing circuit and an armature BEM signal mutual inductor T1, wherein the control circuit includes a main control chip U1, an operational amplifier U2, a Schmitt trigger U5 and a drive chip U4, and the armature BEM signal mutual inductor T1 includes a primary winding and a secondary winding; the voltage stabilizing circuit includes a three-terminal power supply voltage stabilizing chip U3, a diode D1, a capacitor C7 and a capacitor C8.

[0056] like Figure 1 As shown, one end of the primary winding and one end of the secondary winding are grounded at the same time, the other end of the primary winding is connected to the third and seventh pins of the relay K1 to access the BEM ripple signal, the other end of the secondary winding is electrically connected to the sixth pin of the operational amplifier U2, the seventh pin of the operational amplifier U2 is electrically connected to the first pin of the Schmitt trigger U5 after passing through an RC filter circuit, the twelfth pin of the Schmitt trigger U5 is electrically connected to the second pin of the main control chip U1 through a resistor R8, the tenth pin of the main control chip U1 is electrically connected to the first pin of the drive chip U4, the eleventh pin of the main control chip U1 is electrically connected to the second and third pins of the drive chip U4, the seventh and eighth pins of the drive chip U4 are respectively connected to the tenth and fourth pins of the relay K1, thereby driving the relay K1 to control the drive signal for the operation of the window motor M.

[0057] That is, in this embodiment, the armature BEM signal transformer T1 is used to sample the BEM ripple signal of the window motor M when it is rotating, the operational amplifier U2 is used to amplify the signal, and the Schmitt trigger U5 is used to convert the analog signal into a digital pulse signal. The main control chip U1 monitors the pulse width change of the motor BEM signal to determine whether an obstacle is encountered, thereby accurately determining whether the electric window clamps an object during the rising process, and when an obstacle is encountered, the corresponding switch signal is output to the drive chip U4, and then the output of the corresponding channel of the drive chip U4 is used to drive the relay K1 to control the reverse rotation of the window motor M, so that the window is lowered to prevent objects or people from being clamped, thereby realizing the window anti-pinch function.

[0058] like Figure 1 As shown, the anode of the diode D1 is connected to the input voltage signal of 12V and the cathode is electrically connected to the first pin of the three-terminal power supply voltage regulator chip U3 and one end of the capacitor C7 at the same time. The output voltage signal of the third pin of the three-terminal power supply voltage regulator chip U3 is 5V. It is also electrically connected to the first pin of the main control chip U1, the eighth pin of the operational amplifier U2, the fourteenth pin of the Schmitt trigger U5 and one end of the capacitor C8. The second pin of the three-terminal power supply voltage regulator chip U3, the other end of the capacitor C7 and the other end of the capacitor C8 are grounded to supply power to the main control chip U1, the operational amplifier U2 and the Schmitt trigger U5 for normal operation.

[0059] like Figure 1 As shown, the RC filter circuit includes a resistor R17 and a capacitor C13, both of which are electrically connected to the seventh pin of the operational amplifier U2, the other end of the resistor R17 is electrically connected to the first pin of the Schmitt trigger U5, and the other end of the capacitor C13 is grounded.

[0060] In this embodiment, a resistor R13 is further included, one end of the resistor R13 is electrically connected to one end of the primary winding and the other end is electrically connected to the fourteenth pin of the main control chip U1 to implement overcurrent protection when the motor is stalled.

[0061] In this embodiment, it also includes a capacitor C12, a resistor R15 and a capacitor C6. One end of the capacitor C12 is connected to the input voltage signal and the other end is electrically connected to the second pin of the operational amplifier U2, one end of the resistor R15 and one end of the capacitor C6. The other end of the resistor R15 and the other end of the capacitor C6 are electrically connected to the first pin of the operational amplifier U2. The first pin of the operational amplifier U2 is electrically connected to the eighteenth pin of the main control chip U1 via the resistor R12 to realize the automatic window closing function when parking.

[0062] like Figure 2 As shown, in this embodiment, the primary winding includes a primary magnetic ring and a constantan wire wound around the primary magnetic ring 1-2 turns, the constantan wire has a diameter of 1.5 mm and a resistance of 5-10 milliohms, and the secondary winding includes a secondary magnetic ring and an enameled wire wound around the secondary magnetic ring 500-1000 turns, and the diameter of the enameled wire is 0.1 mm.

[0063] like Figure 1 As described above, the present embodiment also includes a window up key and a window down key, which are connected to the 5th and 7th pins of the main control chip through a resistor R4 and a resistor R5, respectively, and are connected in parallel with a resistor R6 and a resistor R7, respectively. In addition, the peripheral circuit of each chip is for the better operation of the chip, and no further description of the electronic components is given, such as the resistor R9 and the resistor R10 connected to the first and second pins of the driver chip U4, the capacitor C4 connected between the fourth and fifth pins, etc.

[0064] In this embodiment, the multifunctional mutual induction electric window anti-pinch controller is a module, and in the entire window control system, a "general distribution, local concentration" control scheme or a separate control scheme is adopted. Figure 4 As shown, the control of the four windows is as one ECU module, or as Figure 5 As shown, the control of the two windows is one ECU module, or as shown Figure 6 A single window is shown as one ECU module.

[0065] Among them, on the basis of the present embodiment 1, the specific process of realizing the anti-pinch function refers to the following embodiment 2.

[0066] Please refer to Figures 1 to 8 , Embodiment 2 of the present invention is:

[0067] The mutual induction electric window anti-pinch control method comprises the following steps:

[0068] S1, collecting the BEM ripple signal of the window motor M;

[0069] In this embodiment, step S1 is to collect the BEM ripple signal by the armature BEM signal transformer T1, and the following step S2 is processed by the main control chip U1.

[0070] S2. Determine whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold. If so, generate an anti-pinch control signal to control the operation of the window motor M.

[0071] In this embodiment, step S2 specifically includes the following steps:

[0072] Read the current position of the window and the key input signal. If the key input signal is a window lifting signal, output a switch signal to drive the window motor M to move up and down. If the window lifting signal is a window rising signal, count up the BEM pulse signal to obtain the real-time position of the window. If the window lifting signal is a window falling signal, count down the BEM pulse signal to obtain the real-time position of the window. The BEM pulse signal is a digital pulse signal obtained after the Schmitt trigger U5 converts the BEM ripple signal.

[0073] Determine whether the time after the window motor M is started reaches the preset delay time. If so, determine whether the real-time position of the window is in the anti-pinch area through the main control chip U1. If so, determine whether the pulse width deformation of the BEM ripple signal is greater than the preset threshold. If so, generate an anti-pinch control signal to control the reversal of the window motor M. The anti-pinch area is between the lowest window rise value and the highest window rise value.

[0074] In this embodiment, the preset delay time is between 40ms and 60ms. Figure 8 As shown in the figure, the preset delay time is 50ms to avoid the impact of instantaneous overshoot on the anti-pinch threshold setting during the initial motor startup. The minimum window rise value range is between 30mm and 80mm from the bottom of the window, and the maximum window rise value range is between 3mm and 5mm from the top of the window. Figure 3 As shown, the minimum window rise value range is when the window rises 50mm from the bottom, and the maximum window rise value range is when the window rises to 4mm from the top, that is, only the middle is the anti-pinch area, and both sides are non-anti-pinch areas.

[0075] In summary, the present invention provides a multifunctional mutual inductance electric window anti-pinch controller and control method, which samples the BEM ripple signal of the window motor M when it rotates through the armature BEM signal mutual inductor T1, and stabilizes the 12V input voltage into a 5V output voltage by the three-terminal power supply voltage regulator chip U3 to supply power to the main control chip U1, the operational amplifier U2 and the Schmitt trigger U5 for normal operation, amplifies the signal through the operational amplifier U2, and converts the analog signal into a digital pulse signal through the Schmitt trigger U5, so as to provide the main control chip U1 to determine whether an obstacle is encountered. When an obstacle is encountered, the corresponding switch signal is output to the drive chip U4, and then the output of the corresponding channel of the drive chip U4 is used to drive the relay K1 to control the reverse rotation of the window motor M, so that the window is lowered to prevent objects or human bodies from being pinched, thereby realizing the window anti-pinch function. A resistor R13 is connected to one end of the primary winding to detect the change of the motor armature current, and the change of the motor armature current is sent to the main control chip U1 to implement overcurrent protection when the motor is blocked. The ripple signal of the motor operation is collected by capacitor C12, and the signal is amplified by resistor R15, capacitor C6 and the internal unit of operational amplifier U2, and then output to the main control chip U1 through the first pin of operational amplifier U2 to realize the automatic window closing function when parking. At the same time, after the window motor M is started, an appropriate delay is performed, and then the BEM ripple signal is detected, so as to avoid the influence of the instantaneous overshoot at the initial stage of motor start-up on the anti-pinch threshold setting; the pulse output and counting scheme of the armature BEM signal transformer T1 can determine the current position of the window in real time, and determine whether the window anti-pinch function is enabled according to the above-determined anti-pinch area.

[0076] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A mutual induction electric window anti-pinch control method, characterized in that: The method is applied to a multifunctional mutual inductance electric window anti-pinch controller, the controller comprising a control circuit and an armature BEM signal mutual inductor T1, the control circuit comprising a main control chip U1, the armature BEM signal mutual inductor T1 comprising a primary winding and a secondary winding; One end of the primary winding and one end of the secondary winding are grounded at the same time, the other end of the primary winding is used to access the BEM ripple signal, and the other end of the secondary winding is electrically connected to one end of the main control chip U1; The main control chip U1 is used to generate an anti-pinch control signal capable of controlling the operation of the window motor M according to the pulse width deformation of the BEM ripple signal; The control circuit also includes an operational amplifier U2, a Schmitt trigger U5 and a driver chip U4; The other end of the secondary winding is electrically connected to the sixth pin of the operational amplifier U2, the seventh pin of the operational amplifier U2 is electrically connected to the first pin of the Schmitt trigger U5 after passing through an RC filter circuit, and the twelfth pin of the Schmitt trigger U5 is electrically connected to the second pin of the main control chip U1; The tenth pin of the main control chip U1 is electrically connected to the first pin of the driving chip U4, the eleventh pin of the main control chip U1 is electrically connected to the second pin and the third pin of the driving chip U4, and the seventh pin and the eighth pin of the driving chip U4 generate a driving signal that can drive the relay K1 to control the operation of the window motor M; The operational amplifier U2 is used to amplify the BEM ripple signal sampled by the armature BEM signal transformer T1; the Schmitt trigger U5 is used to convert the analog signal into a digital pulse signal; The method comprises the steps of: S1, collecting the BEM ripple signal of the window motor M; S2, determining whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold, and if so, generating an anti-pinch control signal to control the operation of the window motor M; The step S2 specifically includes the following steps: Determine whether the time after the window motor M is started reaches the preset delay time. If so, determine whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold. If so, generate an anti-pinch control signal to control the operation of the window motor M. The preset delay time is between 40ms and 60ms. The step S2 specifically includes the following steps: Read the current position of the window and the key input signal. If the key input signal is a window lifting signal, output a switch signal to drive the window motor M to move up and down. If the window lifting signal is a window rising signal, count up the BEM pulse signal to obtain the real-time position of the window. If the window lifting signal is a window falling signal, count down the BEM pulse signal to obtain the real-time position of the window. The BEM pulse signal is a digital pulse signal obtained after the Schmitt trigger U5 converts the BEM ripple signal. Determine whether the real-time position of the window is in the anti-pinch area. If so, determine whether the pulse width deformation of the BEM ripple signal is greater than a preset threshold. If so, generate an anti-pinch control signal to control the reverse of the window motor M. The anti-pinch area is between the lowest value of the window rise and the highest value of the window rise. The lowest value of the window rise ranges from 30 mm to 80 mm when the window rises from the bottom, and the highest value of the window rise ranges from 3 mm to 5 mm when the window rises from the top.

2. The mutual induction electric window anti-pinch control method according to claim 1, characterized in that: It also includes a resistor R13, one end of which is electrically connected to one end of the primary winding and the other end of which is electrically connected to the fourteenth pin of the main control chip U1.

3. The mutual induction electric window anti-pinch control method according to claim 1, characterized in that: Also includes capacitor C12, resistor R15 and capacitor C6; One end of the capacitor C12 is connected to the input voltage signal and the other end is electrically connected to the second pin of the operational amplifier U2, one end of the resistor R15 and one end of the capacitor C6. The other end of the resistor R15 and the other end of the capacitor C6 are electrically connected to the first pin of the operational amplifier U2. The first pin of the operational amplifier U2 is electrically connected to the eighteenth pin of the main control chip U1.

4. The mutual induction electric window anti-pinch control method according to any one of claims 1 to 3, characterized in that: The primary winding includes a primary magnetic ring and a constantan wire wound around the primary magnetic ring for 1-2 turns, the constantan wire has a diameter of 1.5 mm and a resistance of 5-10 milliohms, and the secondary winding includes a secondary magnetic ring and an enameled wire wound around the secondary magnetic ring for 500-1000 turns, the diameter of the enameled wire is 0.1 mm.

5. The mutual induction electric window anti-pinch control method according to any one of claims 1 to 3, characterized in that: It also includes a voltage stabilizing circuit, which includes a three-terminal power supply voltage stabilizing chip U3, a diode D1, a capacitor C7 and a capacitor C8; The anode of the diode D1 is connected to the input voltage signal and the cathode is electrically connected to the first pin of the three-terminal power supply voltage regulator chip U3 and one end of the capacitor C7. The third pin of the three-terminal power supply voltage regulator chip U3 is electrically connected to the first pin of the main control chip U1, the eighth pin of the operational amplifier U2, the fourteenth pin of the Schmitt trigger U5 and one end of the capacitor C8. The second pin of the three-terminal power supply voltage regulator chip U3, the other end of the capacitor C7 and the other end of the capacitor C8 are grounded.

6. The mutual induction electric window anti-pinch control method according to claim 5, characterized in that: The input voltage signal is 12V, and the output voltage signal of the third pin of the three-terminal power supply voltage regulator chip U3 is 5V.

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