A control method for a multifunctional starter

Abstract

The present invention provides a control method for a multifunctional starter, and its top gear protection function includes setting the maximum time of delayed release of the relay to 30S, judging whether the delay time of the relay exceeds 30s; if it exceeds 30s, the relay and the electromagnetic switch are disconnected, and the starter is stopped, and if it does not exceed 30s, the next step is entered; the protection circuit collects the voltage of the electromagnetic switch 50C terminal, records the voltage U1, and after 20-70ms, the relay is turned on, and the voltage U2 of the electromagnetic switch 50C terminal is collected. If U2<U1, it is judged that the electromagnetic switch has been energized; the timer is used for timing, and sampling is performed every 10ms within 300-800ms, and each sampling voltage is greater than the previous 0.12V, and it needs to be satisfied for 6 times in a row; if it is satisfied, it is judged that there is no top gear, the top gear protection function is terminated, the relay is continuously energized, and other protection function judgments are continued; if it is not satisfied, it is judged to be a top gear, the relay and the electromagnetic switch are disconnected, and the starter is stopped. The top gear protection function is set in the protection circuit, and the starter can be powered off in time when the top gear phenomenon occurs, so that the starter is protected from burning.

Description

Technical Field

[0001] The invention relates to the technical field of electronic protection control of a starter, and in particular to a control method for a multifunctional starter. Background Art

[0002] The starter is a short-time working DC motor. It is easy to be damaged if the working time exceeds the prescribed time. During use, the operator often forces the starting motor for a long time, fails to disconnect the starter in time after the engine starts, and other incorrect operating methods, as well as long-term power-on of the starter due to external circuit failure, which will cause the starter to be damaged due to overheating.

[0003] With the continuous development of engine and vehicle technology, high-end commercial vehicles are now beginning to adopt a one-button start function, which is controlled by the vehicle ECU to control the on-off of the starter control end circuit. When the driver presses the start button, the ECU energizes the starter control end, and then the relay coil is energized, the relay contacts are closed, and the electromagnetic switch coil is energized (the pull-in coil generates a current of about 300A-400A). The electromagnetic switch coil generates electromagnetic force and pulls the switch core; on the one hand, the drive gear is shifted out through the shift fork to engage with the engine flywheel ring gear; when the starter has a top tooth, the drive gear is pressed on the ring gear surface and fails to engage with the engine flywheel ring gear, the ECU may continue to supply power (15S or 30S, unless the power is cut off manually), which will cause the pull-in coil of the starter electromagnetic switch to continue to be energized. Since the pull-in coil current reaches about 300A-400A, it will quickly heat up, the coil resistance will quickly increase, and the starter pre-torque will decrease, which will affect the second start, or even overheat and burn. Summary of the invention

[0004] The present invention aims to solve the technical problem in the prior art that the starter is often overheated and burned due to the occurrence of tooth contact between the drive gear and the flywheel ring gear; the present invention provides a control method for a multifunctional starter. After the starter is started, the tooth contact protection function of the protection circuit determines in real time whether the tooth contact phenomenon occurs. When a tooth contact failure occurs, the starter can be powered off in time to protect the electromagnetic switch suction and pull coil of the starter from being burned.

[0005] The present invention is implemented as follows: a control method for a multifunctional starter, including a top gear protection function, wherein the judgment logic of the top gear protection function includes the following steps:

[0006] Step 1: Set the maximum time for the starter relay to be released after a delay of 30 seconds, and determine whether the delay of the relay exceeds 30 seconds; if it exceeds 30 seconds, disconnect the relay and the electromagnetic switch and stop the starter; if it does not exceed 30 seconds, proceed to the next step;

[0007] Step 2: The protection circuit collects the voltage at the electromagnetic switch 50C terminal and records it as voltage U1. The duration of recording voltage U1 is 20-70ms. After 20-70ms, the relay is turned on and the voltage U2 at the electromagnetic switch 50C terminal is collected. If U2 < U1, the protection circuit determines that the electromagnetic switch has been energized.

[0008] Step 3: The timer starts timing, and sampling is performed every 10ms within 300-800ms. The voltage of each sampling is greater than the previous 0.12V. This situation needs to be met for 6 consecutive times. If it is met, it is judged that no top gear phenomenon has occurred, and the top gear protection function is terminated. The relay is continuously energized and other protection function judgments are continued. If it is not met, it is judged that the top gear phenomenon has occurred, and the relay and electromagnetic switch are disconnected, and the starter is stopped.

[0009] Furthermore, the time for recording the voltage U1 in step 2 is 70 ms.

[0010] Furthermore, the sampling duration in step three is 300±15ms.

[0011] Furthermore, it also includes an overrun protection function; if the tooth top phenomenon does not occur, the overrun protection function is entered; the judgment logic of the overrun protection function includes the following steps:

[0012] Step 1: The protection circuit collects the voltage U3 at the C end of the electromagnetic switch 50 at this time, and determines whether U3 is greater than 24V;

[0013] Step 2: If U3>24V, perform 30 sampling cycles continuously;

[0014] Step 3: If the voltage sampled each time is greater than the sampling voltage of the previous point, and each sampling is greater than 24V, then disconnect the relay, turn off the electromagnetic switch, and stop the starter; if the above conditions are not met, that is, U3 is less than 24V once, then restart the judgment logic of the overrun protection function.

[0015] Furthermore, it also includes a time-delay protection function; if the judgment logic of the overrun protection function is not satisfied within 30 seconds, that is, U3 is always less than 24V, the time-delay protection function is entered, and the electromagnetic switch 50C terminal is forcibly controlled to cut off the power.

[0016] The advantages of the present invention are as follows: the control method of the multifunctional starter of the present invention sets a top gear protection function in the protection circuit, and when the top gear phenomenon occurs, the starter can be powered off in time to protect the electromagnetic switch suction and pull coil of the starter from burning. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with embodiments with reference to the accompanying drawings.

[0018] Figure 1It is a cross-sectional view of the starter of the present invention.

[0019] Figure 2 It is a circuit principle diagram of the protection circuit, relay, electromagnetic switch and motor of the present invention.

[0020] Figure 3 It is a judgment flow chart of the control method of the multifunctional starter of the present invention.

[0021] Figure 4 This is a data collection diagram when the top tooth protection is triggered by the present invention.

[0022] Figure 5 This is a data collection diagram when the overrun protection is triggered by the present invention.

[0023] Starter 100, relay 1, electromagnetic switch 2, holding coil 21, suction and pulling coil 22, stop iron 23, moving iron core 24, shift fork 3, motor 4, moving shaft 41, driving gear 42, battery 5, electric lock door 6. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0025] See also Figure 1-5 As shown, the starter 100 of the present invention includes a relay 1, an electromagnetic switch 2, a shift fork 3, a motor 4, and a battery 5; the output end of the motor 4 includes a moving shaft 41, and the output end of the moving shaft 41 is equipped with a driving gear 42 for meshing with the flywheel ring gear of the engine.

[0026] As attached Figure 2 As shown, the protection circuit is installed on the relay 1; the 50C terminal is connected to the battery 5 and the relay 1 through the electric lock door 6; the electromagnetic switch 2 has a 30 terminal and a 50 terminal, and the 30 terminal is connected to the battery 5; the positive terminal of the relay 1 is connected to the 50C terminal, and the negative terminal is grounded through the protector; the positive terminal of the relay contact is connected to the 30 terminal, and the negative terminal is connected to the 50 terminal; the electromagnetic switch 2 also includes a holding coil 21 and a pull-in coil 22, and the 50 terminal is respectively connected to the positive terminal of the pull-in coil 22 and the positive terminal of the holding coil 21.

[0027] When the driving gear 42 is meshed with the flywheel gear ring smoothly: after the battery 5 energizes the electromagnetic switch 50C end, the protection circuit collects the voltage U1 at the electromagnetic switch 50C end, and then the relay 1 is energized, the electromagnetic switch 50C end obtains the voltage, and the pull-in coil 22 and the holding coil 21 of the electromagnetic switch 2 will generate a current of about 300A-400A. Due to the internal resistance of the battery 5, the battery voltage will drop slightly. At this time, the voltage at the 50C end will also drop slightly, and the protection circuit records the drop. The voltage after U2 is U2, and U2<U1; the protection circuit will determine that the electromagnetic switch 2 has been energized, and the holding coil 21 and the suction and pulling coil 22 of the electromagnetic switch 2 are energized to generate electromagnetic attraction on the stop iron 23. The moving iron core 24 in the electromagnetic switch 2 is moved toward the stop iron 23 by the electromagnetic force, thereby pulling the shift fork 3 to rotate, so that the shift fork 3 drives the moving shaft 41 and the driving gear 42 arranged on the moving shaft 41 to extend out, and smoothly mesh with the flywheel ring gear, and the starter 100 pries the flywheel ring gear to rotate rapidly.

[0028] When the driving gear 42 and the flywheel gear ring are in a toothing phenomenon: the driving gear 42 and the flywheel gear ring are not aligned. At this time, the motor 4 is connected in series with the pull coil 22, which will generate a small slow-turning torque and drive the driving gear 42 to rotate. Under normal circumstances, the driving gear 42 will be staggered with the tooth surface of the flywheel gear ring to achieve meshing, and then the starter 100 starts to operate with a large torque. At this time, the instantaneous current of the starter 100 is nearly 5-8 times that of the electromagnetic switch 2, usually as high as 1200-2000A, so the voltage of the entire system will drop sharply. When the starter pries the flywheel gear ring to rotate, the current gradually decreases, and the voltage begins to rise. In this recovery process, sampling is performed every 10ms within 300±15ms from the start of timing. If the voltage of each sampling is greater than the previous 0.12V, this situation must be met 6 times (greater than 0.72V in total). This recovery process is consistent with the voltage change when toothing occurs (refer to the attached Figure 4 If the situation is completely different from that shown in the figure, it means that the top tooth phenomenon has not occurred.

[0029] Based on this, the present invention provides a control method for a multifunctional starter, including a top gear protection function, an overrunning protection function, and a time delay protection function.

[0030] The top tooth protection function is used to determine whether the drive gear 42 is meshed with the flywheel gear ring smoothly after the top tooth occurs. The judgment logic of the top tooth protection function includes the following steps:

[0031] Step 1: Set the maximum time for the delayed release of the relay 1 of the starter 100 to 30 seconds, and determine whether the delay time of the relay 1 exceeds 30 seconds; if it exceeds 30 seconds, disconnect the relay 1 and the electromagnetic switch 2, and stop the starter 100; if it does not exceed 30 seconds, proceed to the next step;

[0032] Step 2: The protection circuit collects the voltage at the C terminal of the electromagnetic switch 50 and records it as voltage U1. The duration of recording voltage U1 is 20-70ms. After 20-70ms, the relay 1 is turned on and the voltage U2 at the C terminal of the electromagnetic switch 50 is collected. If U2 < U1, the protection circuit determines that the electromagnetic switch 2 has been energized.

[0033] Step 3: The timer starts timing, and sampling is performed every 10ms within 300-800ms. The voltage of each sampling is greater than the previous 0.12V. This situation needs to be met for 6 consecutive times; if it is met, it is judged that no top gear phenomenon has occurred, and the top gear protection function is terminated. Relay 1 is continuously energized and other protection function judgments are continued; if it is not met, it is judged that the top gear phenomenon has occurred, and the relay 1 and the electromagnetic switch 2 are disconnected, and the starter 100 is stopped.

[0034] In the present invention, based on the above judgment logic, as shown in the attached Figure 4 As shown, in the time interval of 300-800ms, if the voltage U2 does not have a rising process and the rising amplitude does not reach the set 0.72V, it is judged as a top tooth, and relay 1 is turned off.

[0035] In the present invention, based on the above judgment logic, within the time interval of 300-800ms, the voltage U2 has a rising process, and the 6 sampling voltages all have a rise of 0.12V, and the rise amplitude reaches the set 0.72V. It is judged that no top tooth phenomenon occurs, the top tooth protection function is terminated, and relay 1 is continuously energized.

[0036] In step 2 of the present invention, the time for recording the voltage U1 in the top tooth protection function is preferably 70 ms, and the time length is determined according to the initialization and hardware response time.

[0037] In step three of the present invention, the sampling time in the top tooth protection function is preferably 300±15ms. The sampling time is determined according to the tolerance and application conditions of the electromagnetic switch coils of starters of different specifications. According to statistical analysis based on a large amount of actual collected data, the main contact closing time of the electromagnetic switch 2 is usually 10~80ms. Taking into account the slow mechanical action under extremely low temperatures, the longest time will generally not exceed 200ms. Therefore, considering the safety margin, the judgment time is appropriately extended and set to 300±15ms. If the judgment time is too long, the suction and pull coil 22 will overheat and affect the second starting engagement.

[0038] The control method of the multifunctional starter of the present invention has the following beneficial technical effects: a top gear protection function is provided in the protection circuit, and when a top gear failure occurs, the starter 100 can be powered off in time to protect the electromagnetic switch pull coil 22 of the starter 100 from burning out.

[0039] In the present invention, if the tooth top phenomenon does not occur, the overrun protection function is entered. The overrun protection function is used to judge that after the starter 100 starts the engine, the starter 100 is powered off in time, shortening the overrunning working time of the starter 100, preventing the starter 100 from failing due to being dragged back by the engine, and improving the service life of the starter 100 and the battery 5.

[0040] The judgment logic of the overrun protection function includes the following steps:

[0041] Step 1: The protection circuit collects the voltage U3 at the C end of the electromagnetic switch 50 at this time, and determines whether U3 is greater than 24V;

[0042] Step 2: If U3>24V, perform 30 sampling cycles continuously;

[0043] Step 3: If the voltage U3 sampled each time is greater than the previous sampled voltage, and each sampling is U3>24V; then disconnect the relay 1, turn off the electromagnetic switch 2, and stop the starter 100; if the above situation is not met, that is, there is a time when U3<24V, then restart the judgment logic of the overrun protection function.

[0044] The present invention also includes a time-delay protection function; the time-delay protection function is used to cut off the power supply of the starter 100 when the continuous working time of the starter 100 reaches the rated working time, thereby preventing the electromagnetic switch 2 or the motor from being burned, and preventing the battery 5 from being over-discharged and damaged prematurely.

[0045] In the judgment of the overrun protection function, if the judgment logic of the overrun protection function is not satisfied within 30 seconds, that is, the U3 counter has not accumulated to 30 times, the delay protection function is entered and the electromagnetic switch 50C terminal is forced to be powered off.

[0046] In the present invention, the protection circuit is composed of the following parts: an electronic chip with a program package, a top gear state detection module, an overvoltage detection module, and a delayed power-off control module. The top gear state detection module is used to implement the top gear protection function, the overvoltage detection module is used to implement the overvoltage protection function, and the delayed power-off control module is used to implement the delayed protection function.

[0047] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A control method for a multifunctional starter, characterized in that: It includes a top tooth protection function, and the judgment logic of the top tooth protection function includes the following steps: Step 1: Set the maximum time for the starter relay to be released after a delay of 30 seconds, and determine whether the delay of the relay exceeds 30 seconds; if it exceeds 30 seconds, disconnect the relay and the electromagnetic switch and stop the starter; if it does not exceed 30 seconds, proceed to the next step; Step 2: The protection circuit collects the voltage at the electromagnetic switch 50C terminal and records it as voltage U1. The duration of recording voltage U1 is 20-70ms. After 20-70ms, the relay is turned on and the voltage U2 at the electromagnetic switch 50C terminal is collected. If U2 < U1, the protection circuit determines that the electromagnetic switch has been energized. Step 3: The timer starts timing, and within 300±15ms, sampling is performed every 10ms. The voltage of each sampling is greater than the previous 0.12V. This situation needs to be met for 6 consecutive times. If it is met, it is judged that no top gear phenomenon has occurred, and the top gear protection function is terminated. The relay is continuously energized and other protection function judgments are continued. If it is not met, it is judged that the top gear phenomenon has occurred, and the relay and electromagnetic switch are disconnected, and the starter is stopped.

2. The control method of the multifunctional starter according to claim 1, characterized in that: The time for recording the voltage U1 in step 2 is 70ms.

3. The control method of the multifunctional starter according to claim 1, characterized in that: It also includes an overrun protection function; if the tooth top phenomenon does not occur, the overrun protection function is entered; the judgment logic of the overrun protection function includes the following steps: Step 1: The protection circuit collects the voltage U3 at the C end of the electromagnetic switch 50 at this time, and determines whether U3 is greater than 24V; Step 2: If U3>24V, perform 30 sampling cycles continuously; Step 3: If the voltage sampled each time is greater than the sampling voltage of the previous point, and each sampling is greater than 24V, then disconnect the relay, turn off the electromagnetic switch, and stop the starter; if the above conditions are not met, that is, U3 is less than 24V once, then restart the judgment logic of the overrun protection function.

4. The control method of the multifunctional starter as claimed in claim 3, characterized in that: It also includes a time-delay protection function; if the judgment logic of the overrun protection function is not satisfied within 30 seconds, that is, U3 is always less than 24V, the time-delay protection function is entered, and the electromagnetic switch 50C terminal is forced to be powered off.

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