A motor control method, and a corresponding projection structure, vehicle lights, and vehicle.

Abstract

One problem addressed by an embodiment of the present invention is reducing the delay when a motor stops. The present invention provides a control method, a corresponding projection structure, a vehicle headlight, and a vehicle. The motor according to the present invention has a control unit, and the method includes the following steps: the control unit outputs current to the motor based on a current pulse cycle to control the rotation of the motor; wherein the current pulse cycle includes a motion period, a transition period, and an interval period, the motion period passing through the transition period and then entering the interval period. The advantage of the present invention is that by employing a transition period, power is no longer supplied to the motor before reaching the target position, and inertia allows the motor to stop directly at the target position, reducing the delay caused by motor overshoot, and improving projection quality by avoiding blurred images caused by the rotation of the projected motor.

Description

Technical Field

[0001] This invention relates to the field of projection technology, specifically to a motor control method, a projection structure, and corresponding vehicle lights and vehicles. Background Technology

[0002] When using a stepper motor for projection control, the motor needs to rotate and stop periodically. Due to inertia, the motor will oscillate back and forth after receiving a stop signal, requiring a certain delay before it truly stops at the target position. (Reference) Figure 2 and Figure 3 For example Figure 2 The current waveform shown corresponds to Figure 3 The diagram illustrates the rotation. When the current outputs a complete sine wave, the motor rotor rotates from the initial position S to the target position D. Subsequently, the current becomes a constant flat wave. Due to inertia, the rotor oscillates back and forth near the target position D, requiring a period of time to truly stabilize at D. Therefore, a relatively long delay is needed. This prolongs the cycle time and also results in a less than ideal projection effect. Summary of the Invention

[0003] In view of this, one of the problems addressed by an embodiment of the present invention is to reduce the delay when the motor stops.

[0004] According to one aspect of the present invention, a method for controlling the movement of a motor is provided, wherein the motor has a control unit, the method comprising the following steps:

[0005] The control unit outputs current to the motor based on the current pulse cycle to control the rotation of the motor;

[0006] The current pulse cycle includes a motion period, a transition period, and an interval period. The motion begins after passing through the transition period and then enters the interval period.

[0007] By employing a transition period, the delay caused by inertia due to the motor stopping directly during the interval period is reduced.

[0008] According to the method of the present invention, the method further includes the following steps:

[0009] During the operation period, a variable current is output to control the motor to rotate continuously;

[0010] During the transition period and the interval period, a stable current is continuously output to stop the output torque.

[0011] A stable current is output during the transition period so that the motor can stop rotating during the transition period, reducing the delay time in the later stage.

[0012] According to the method of the present invention, wherein the motor is a stepper motor, the method further includes the following steps:

[0013] The magnetic poles of the motor stop rotating when the transition period is reached, while the motor rotor continues to rotate to the target position and then stops during the transition period.

[0014] According to the method of the present invention, the method further includes the following steps:

[0015] -The magnetic poles transition from their transitional positions to the target positions after the rotor reaches the target positions.

[0016] Once the magnetic poles reach the target position, the rotor can be stabilized at that position and will no longer rotate back and forth. In other words, it will remain stationary and will not oscillate due to inertia.

[0017] According to the method of the present invention, the current pulse period is related to the frequency of change of the current.

[0018] According to the method of the present invention, the duration of the transition period is related to the current pulse period and the load of the motor.

[0019] According to the method of the present invention, the control unit is further configured to control a light source, and the method further includes the following steps:

[0020] The control unit controls the motor and the light source, so that the light source is lit during the interval of the motor and turned off during the motor's operation and transition periods.

[0021] According to this solution, the motor will not rotate while the light source is lit, thus ensuring that the lighting effect of the light source is not affected.

[0022] According to the method of the present invention, the method further includes the following steps:

[0023] After receiving the trigger signal, the control unit outputs current to the motor based on the current pulse period to control the rotation of the motor.

[0024] According to the method of the present invention, the duration of the transition period and / or the motor rotation angle can be obtained based on measurement.

[0025] According to another embodiment of the present invention, a projection structure is also provided, wherein the projection structure includes a motor, a control unit, and a light source, wherein the projection structure uses the method described above to control the motor in the projection structure.

[0026] According to another aspect of the invention, a vehicle lamp is also provided, the vehicle lamp including the projection structure.

[0027] According to another aspect of the invention, a vehicle is also provided, the vehicle including the vehicle lights.

[0028] Compared with the prior art, the present invention has the following advantages: by adopting a transition period, the motor is no longer powered before reaching the target position, and the inertia is used to make the motor stop directly at the target position, reducing the delay caused by motor overshoot, and improving the projection quality by avoiding the blurry image caused by the rotation of the projection motor. Attached Figure Description

[0029] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0030] Figure 1 A three-dimensional structural diagram of a projection structure according to an embodiment of the present invention is shown;

[0031] Figure 2 This diagram illustrates the pulse waveform of a motor control circuit according to the prior art.

[0032] Figure 3 A schematic diagram illustrating the rotational position of an electric motor according to the prior art is shown;

[0033] Figure 4 A schematic diagram of the current pulse waveform of a two-phase current of a motor according to an embodiment of the present invention is shown.

[0034] Figure 5 A schematic diagram illustrating a motor rotation position according to an embodiment of the present invention is shown;

[0035] Figure 6 A schematic diagram of the current pulse waveform of the three-phase current of a motor according to an embodiment of the present invention is shown.

[0036] Figure 7 A schematic diagram illustrating the steps of a control method according to an embodiment of the present invention is shown.

[0037] List of reference numerals in the attached diagram:

[0038] 1 First support 2 Lens group 3 Film Department 4 light source 5 motor 6 Control Department 7 Transmission section 8 Second support 9 PCB board 10 support plate Detailed Implementation

[0039] Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be more thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0040] An embodiment of the present invention discloses a projection structure and a method for projection, as well as a vehicle lamp having the projection structure and a vehicle using the vehicle lamp.

[0041] Among them, reference Figure 1 . Figure 1 A three-dimensional schematic diagram of a projection structure according to an embodiment of the present invention is shown.

[0042] according to Figure 1 The projection structure of the illustrated embodiment includes a light source 4, a motor 5, and a control unit 6. Preferably, the projection structure further includes a first support 1, a lens group 2, a film section 3, and a second support 8.

[0043] The light source 4, the film section 3, and the lens group 2 form a projection light path. The film section 3 is driven to rotate by the motor 5; the lens group 2 includes at least one lens, and the at least one lens is housed in the first bracket 1; the control unit 6 is used to control the motor 5 and / or the light source 4.

[0044] The control unit 6 can typically be implemented using a microcontroller unit (MCU). Furthermore, it can be physically separated from the input receiving components, such as sensor 601.

[0045] In one embodiment of the present invention, the method includes step S1.

[0046] In step S1, the control unit 6 outputs current to the motor 5 based on the current pulse cycle to control the rotation of the motor 5.

[0047] refer to Figure 4 and Figure 5 According to one embodiment of the present invention, the following method is adopted: Figure 4 The waveform shown is described above. The current pulse period includes a motion period t1, a transition period ta, and an interval period t2. The motion period t1 passes through the transition period ta before entering the interval period t2.

[0048] Figure 6A schematic diagram of the current pulse cycle for a three-phase current according to this scheme is shown. Those skilled in the art will understand that different specifications of stepper motors can use different parameters such as two-phase current or three-phase current. As long as the waveform of the pulse current used includes the motion period, transition period, and interval period as described in this scheme, its motor operation can be considered the same as or similar to that of this scheme.

[0049] Specifically, refer to Figure 7 Step S1 further includes steps S11 and S12.

[0050] In step S11, during the motion period, the control unit 6 outputs a sinusoidal changing current, and the rotor of the motor 5 starts to rotate from the initial position S. Then, in step S12, upon reaching the transition period ta, that is... Figure 5 At position A, control unit 6 begins to output a constant current. At this time, the motor rotor continues to rotate due to inertia until it reaches the target position D and comes to rest at this position. Subsequently, it remains stationary at the beginning of the interval period t1 until the next sine wave arrives.

[0051] Subsequently, in the next cycle, with the current target D as the new starting position, the sequence of steps S11 and S12 is repeated to output current and thus control motor 5.

[0052] Those skilled in the art will understand that when the control unit 6 controls the output of a constant current, the rotor power of the motor 5 disappears, and it continues to move forward only by inertia.

[0053] According to a preferred embodiment of the present invention, the method further includes step S13.

[0054] In step S13, the phase angle of motor 5 stops moving during the transition period, while the rotor of motor 5 continues to rotate to the target position and then stops during the transition period. Here, the phase angle of the motor is the angle between the rotor magnetic pole and the main magnetic pole.

[0055] Specifically, when controller 6 starts outputting a constant current corresponding to the transition period ta according to the current pulse cycle, the phase angle of motor 5 stops changing, and it no longer outputs torque. Simultaneously, the rotor of motor 5 continues to move forward due to inertia and stops at the target position.

[0056] That is, reference Figure 4 and Figure 5 At the start of the transition period, the rotor of motor 5 is located at point A. During the transition period, the phase angle stops changing from point A, while the rotor continues to move forward using inertia and reaches the target position point D.

[0057] More preferably, according to the preferred embodiment of this invention, the method further includes step S14 after step S13.

[0058] In step S14, after the rotor of motor 5 reaches the target position, the phase angle of motor 5 is switched from the transition phase angle during the transition period to the target phase angle corresponding to the target position.

[0059] That is, reference Figure 4 and Figure 5 After the rotor reaches the target position D, the phase angle, which originally stopped changing during the transition period, rapidly rotates at the end of the transition period ta, reaching the target phase angle corresponding to the target position D. That is, the current pulse portion that rapidly returns to the central axis at the end of the transition period ta.

[0060] Preferably, the target phase angle is the same as the phase angle of the motor when it is in the starting position S.

[0061] The current pulse period is related to the frequency of the current change. That is, by changing the frequency of the output current change, the length of the current pulse period corresponding to motor 5 can be controlled.

[0062] Preferably, according to another embodiment of the present invention, the control unit 6 is further used to control a light source 4, and the method according to this embodiment further includes step S2.

[0063] In step S2, the control unit 6 controls the motor 5 and the light source 4, so that the light source 4 is lit during the interval of the motor 5 and turned off during the operation and transition periods of the motor 5.

[0064] Specifically, in combination Figure 1 In the projection structure shown, during the motion period t1, the control unit 6 controls the motor 5 to rotate, thereby rotating the film section 3. At this time, the light source 4 is off. Subsequently, during the transition period ta, the control unit 6 controls the output of a constant current. The motor 5 loses its power and continues to move by inertia, stopping when it reaches the target position corresponding to the magnetic pole. At this time, the light source 4 remains off. The light source 4 is off during both the motion period t1 and the transition period ta, and does not project the rotation process of the film section 3 driven by the motor 4. Then, during the interval period t2, the control unit 6 continues to output a constant current. Since the motor 5 has no power, it remains stationary at the target position. The light source 4 turns on, illuminating the film in the film section located in the projection channel, thus projecting the film image.

[0065] Preferably, according to another embodiment of the present invention, the method further includes step S3.

[0066] In step S3, after receiving the trigger signal, the control unit 6 outputs current to the motor 5 based on the current pulse period to control the rotation of the motor 5.

[0067] The trigger signal includes various types of information that the control unit 6 can receive.

[0068] Preferably, the control unit 6 acquires input information through a detection device such as a sensor.

[0069] Preferably, the input information obtained by the control unit 6 includes, but is not limited to, at least one of the following:

[0070] 1) Film positioning information; for example, the starting position information of the film; or the position information of each film, etc.

[0071] 2) Vehicle speed information; for example, the current vehicle speed in hours; or, for example, vehicle speed rating information, etc.

[0072] 3) Vehicle operation information, such as pressing the brake, opening the door, etc.

[0073] Preferably, the control unit 6 determines whether to trigger the start or stop of the projection structure based on the input information; or, the control unit 6 controls the running time and running interval of the projection structure based on the input information.

[0074] According to the method of the present invention, the duration of the transition period is related to the current pulse period and the load of the motor. Furthermore, the duration of the transition period and / or the motor rotation angle can be obtained based on measurement.

[0075] According to a preferred embodiment of this invention, the projection structure may include an infrared sensor 601. The infrared sensor 601 is used to detect one or more specific locations on the film portion 3. In one example, the front of the infrared sensor may have two protruding arms, which can detect specific structures on the flywheel, such as depressions or protrusions on the flywheel surface, when the flywheel rotates between these arms.

[0076] A film is loaded onto the motor 5, and pulse information corresponding to the actual position of the motor is obtained based on the sensing information of the infrared sensor 601. By adjusting multiple transition periods, a suitable transition period ta (or the motor rotation angle θA corresponding to the transition period) is finally determined, and the current pulse waveform of the control current, which corresponds to the current pulse period, is finally determined by the control unit 6 under similar load conditions.

[0077] Compared with the prior art, the present invention has the following advantages: by adopting a transition period, the motor is no longer powered before reaching the target position, and the inertia is used to make the motor stop directly at the target position, reducing the delay caused by motor overshoot, and improving the projection quality by avoiding the blurry image caused by the rotation of the projection motor.

[0078] Those skilled in the art will understand that various types of sensors, not limited to infrared sensors, can be used to detect the position of the flywheel. For example, a magnetic sensor can be used, with a corresponding magnetic structure installed on the flywheel. The position can be determined based on the different magnetic forces generated when the flywheel rotates. Those skilled in the art can determine the appropriate sensor based on the actual situation and requirements, which will not be elaborated upon here.

[0079] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be embraced within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices recited in the system claims may also be implemented by a single unit or device in software or hardware. The terms "first," "second," etc., are used to indicate names and do not indicate any particular order.

Claims

1. A method for controlling the movement of a motor (5), wherein, The motor (5) has a control unit, wherein the method includes the following steps: - The control unit outputs current to the motor (5) based on the current pulse cycle to control the rotation of the motor (5); The current pulse cycle includes a motion period, a transition period, and an interval period, and the motion begins after passing through the transition period and then enters the interval period. The method further includes the following steps: - During the motion period, a variable current is output to control the motor (5) to rotate continuously; - During the transition period and the interval period, a constant current is continuously output to stop the output torque.

2. The method according to claim 1, wherein, The motor (5) is a stepper motor, and the method further includes the following steps: - The phase angle of the motor (5) stops moving during the transition period, while the rotor of the motor (5) continues to rotate to the target position and then stops during the transition period; wherein, the phase angle of the motor (5) is the angle between the rotor magnetic pole and the main magnetic pole.

3. The method according to claim 2, wherein, The method also includes the following steps: - After the rotor of the motor (5) reaches the target position, the phase angle of the motor (5) is changed from the transition phase angle during the transition period to the target phase angle corresponding to the target position.

4. The method according to any one of claims 1 to 3, wherein, The current pulse period is related to the frequency of the current change.

5. The method according to any one of claims 1 to 3, wherein, The duration of the transition period is related to the current pulse period and the load of the motor (5).

6. The method according to any one of claims 1 to 3, wherein, The control unit is also used to control a light source, and the method further includes the following steps: The control unit controls the motor (5) and the light source (4) so ​​that the light source (4) is lit during the interval of the motor (5) and turned off during the operation and transition periods of the motor (5).

7. The method according to any one of claims 1 to 3, wherein, The method further includes the following steps: After receiving the trigger signal, the control unit outputs current to the motor based on the current pulse period to control the rotation of the motor (5).

8. The method according to any one of claims 1 to 3, wherein, The duration of the transition period and / or the motor rotor angle can be obtained based on measurements.

9. A projection structure, wherein, The projection structure includes a motor (5), a control unit, and a light source (4), wherein the projection structure uses the method described in any one of claims 1 to 8 to control the motor (5) in the projection structure.

10. A vehicle lamp, the vehicle lamp comprising the projection structure as described in claim 9.

11. A vehicle comprising the headlights as claimed in claim 10.

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