Starter performance matching test method under low temperature condition

Abstract

The invention discloses a starter performance matching test method under a low-temperature condition, and belongs to the technical field of gasoline engine starters. Comprising the following steps that S1, an existing starter A is installed on an engine, and the whole machine is placed in a low-temperature environment; s2, connecting the devices; s3, checking the state; s4, a fuel injector connector is pulled out, an engine is prevented from being started, the S end of the starter A is powered on, an oscilloscope is used for recording starting data, and the starting rotating speed is calculated according to the current change condition of the B + end of the starter A; s5, a starter performance curve is tested, and the low-temperature starting resistance moment of the engine is obtained according to the rotating speed of the engine; and S7, selecting a suitable starter platform according to the calculated starter power required by the engine, testing a performance curve of the starter, adjusting the gear transmission ratio of the starter, adjusting the power of the starter, and completing selection of the transmission ratio. According to the starter performance matching test method under the low-temperature condition, the starter power and the starter transmission ratio which are most suitable for the engine can be selected.

Description

Technical Field

[0001] The invention belongs to the technical field of gasoline engine starters, and in particular relates to a starter performance matching test method under low temperature conditions. Background Art

[0002] Whether the gasoline engine starter selection is reasonable mainly considers whether the starter can start the engine smoothly under low temperature conditions. At present, all car manufacturers and engine manufacturers use benchmarking to determine the starter power when matching starters. According to the actual low-temperature starting effect, the starter selection and gear ratio are confirmed to be reasonable. The matching method is physical verification, and unreasonable selection may occur. Summary of the invention

[0003] In order to solve the above problems, the present invention further provides a starter performance matching test method under low temperature conditions, which can make the starter selection more reasonable.

[0004] The technical solution adopted by the present invention is:

[0005] A method for testing starter performance matching under low temperature conditions comprises the following steps:

[0006] S1. Install the existing starter A on the engine and place the whole engine in a low temperature environment;

[0007] S2. Check the status of the engine and starter A, and connect the test equipment;

[0008] S3. Check the battery status, confirm the voltage and internal resistance, measure and record the internal resistance of the B+ terminal wiring harness of starter A, and record the oil temperature;

[0009] S4. Unplug the injector connector to prevent the engine from starting, power up the S terminal of starter A, use an oscilloscope to record the starting data, and calculate the starting speed based on the current change at the B+ terminal of starter A;

[0010] S5. Test the starter performance curve and obtain the engine low temperature starting resistance torque according to the engine speed;

[0011] S6. Calculate the power output of the starter motor for low-temperature starting of the engine according to the motor power formula:

[0012] S7. Select a suitable starter platform based on the calculated starter power required by the engine, test the starter performance curve, adjust the starter gear ratio, and complete the starter power and transmission ratio selection.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The present invention can select the starter power and starter transmission ratio most suitable for the engine through the starter performance matching test method under low temperature conditions.

[0015] The present invention connects an existing starter to an engine to conduct a low-temperature test to determine the low-temperature resistance torque of the engine. According to the empirical starting speed of a gasoline engine of 100 to 120 r / min, a starter power platform is selected by calculating through a motor power formula. By measuring the starter low-temperature power curve of the selected platform, a suitable starter gear ratio is determined, and the starter selection is more reasonable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the engine low temperature resistance test circuit diagram of the present invention;

[0017] Figure 2 This is an example diagram of the B+ terminal current change and the engine speed calculation method of the present invention;

[0018] Figure 3 is a starter performance curve and a starter operating point selection example diagram of the present invention; DETAILED DESCRIPTION

[0019] In order to better understand the purpose, structure and function of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0020] The present invention provides a method for testing the performance matching of a starter under low temperature conditions. The method comprises the following steps: connecting an existing starter to an engine to conduct a low temperature test to determine the low temperature resistance torque of the engine; selecting a starter power platform by calculating a motor power formula based on an empirical starting speed of 100 to 120 r / min for a gasoline engine; and determining a suitable starter gear ratio by measuring a starter low temperature power curve of the selected platform, thereby making the starter selection more reasonable.

[0021] The following steps are involved:

[0022] S1. Install the existing starter A on the engine (by customizing simple tooling, etc.), and place the entire machine in a low temperature environment (set the ambient temperature according to the set cold start temperature);

[0023] S2. Check the status of the engine and starter A, such as Figure 1 Connect the test equipment as shown;

[0024] The B+ terminal and S terminal of the starter are both connected to the battery, and an ammeter is connected to the circuit connecting the B+ terminal of the starter A to the battery, and the ammeter is electrically connected to the oscilloscope.

[0025] S3. Check the battery status, confirm the voltage and internal resistance, measure the internal resistance of the B+ terminal wiring harness of starter A and record it (refer to the vehicle status), and record the oil temperature;

[0026] S4. Unplug the injector connector to prevent the engine from starting. Power is supplied to the S terminal of starter A. The starter gear pops out and meshes with the flywheel and drags the engine to rotate. Use an oscilloscope to record the starting data. Calculate the starting speed based on the current change at the B+ terminal of starter A. The following is an example of the current change at the B+ terminal and the method for calculating the engine speed: Figure 2 As shown;

[0027] S5. Place starter A in a refrigerator and freeze it to the temperature of the previous test. Take it out and quickly install it on the starter test bench. Set the starting boundary according to the battery voltage, internal resistance, and internal resistance of the B+ terminal harness measured in the previous test. Test the starter performance curve and obtain the engine low-temperature starting resistance torque based on the engine speed.

[0028] S6. Calculate the power output of the starter motor for low-temperature starting of the engine according to the motor power formula:

[0029] Wherein, n is the engine required low temperature starting speed, T is the engine low temperature resistance torque, and P is the power output of the starter required for engine low temperature starting.

[0030] S7. Select a suitable starter platform based on the calculated starter power required by the engine, place the platform starter B in a refrigerator, freeze it to the temperature of the previous test, take it out and quickly install it on the starter test bench, set the starting boundary according to the battery voltage, internal resistance, and B+ terminal harness internal resistance measured in the previous test, test the starter performance curve, adjust the starter gear ratio, and make the starter work in the area to the left of the maximum power point of the starter performance curve at low temperature, such as Figure 3 At this time, the starter motor dragging engine speed should be greater than 120r / min, and the starter motor power and transmission ratio selection are completed.

[0031] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A method for testing starter performance matching under low temperature conditions, characterized in that: The following steps are involved: S1. Install the existing starter A on the engine and place the whole engine in a low temperature environment; S2. Check the status of the engine and starter A, and connect the test equipment; S3. Check the battery status, confirm the voltage and internal resistance, measure and record the internal resistance of the B+ terminal wiring harness of starter A, and record the oil temperature; S4. Unplug the injector connector to prevent the engine from starting, power up the S terminal of starter A, use an oscilloscope to record the starting data, and calculate the starting speed based on the current change at the B+ terminal of starter A; S5. Test the starter performance curve and obtain the engine low temperature starting resistance torque according to the engine speed; S6. Calculate the power output of the starter motor for low-temperature starting of the engine according to the motor power formula: S7. Select a suitable starter platform based on the calculated starter power required by the engine, test the starter performance curve, adjust the starter gear ratio, and complete the starter power and transmission ratio selection.

2. The method for testing the performance matching of a starter under low temperature conditions according to claim 1, characterized in that: The device connection method in S2 is: The B+ terminal and S terminal of the starter are both connected to the battery, an ammeter is connected to the circuit connecting the B+ terminal of starter A to the battery, and the ammeter is electrically connected to the oscilloscope.

3. The method for testing the performance matching of a starter under low temperature conditions according to claim 1, characterized in that: The specific steps of S5 are: Place starter A in a refrigerator and freeze it to the temperature of the previous test. Take it out and quickly install it on the starter test bench. Set the starting boundary according to the battery voltage, internal resistance, and B+ terminal harness internal resistance measured previously. Test the starter performance curve and obtain the engine low-temperature starting resistance torque based on the engine speed.

4. The method for testing the performance matching of a starter under low temperature conditions according to claim 1, characterized in that: The calculation formula in S6 is: Wherein, n is the engine required low temperature starting speed, T is the engine low temperature resistance torque, and P is the power output of the starter required for engine low temperature starting.

5. The method for testing the performance matching of a starter under low temperature conditions according to claim 4, characterized in that: The specific steps of S7 are: Select a suitable starter platform based on the calculated starter power required by the engine, place the platform starter B in a refrigerator, freeze it to the temperature of the previous test, take it out and quickly install it on the starter test bench, set the starting boundary according to the battery voltage, internal resistance, and B+ terminal harness internal resistance measured in the previous test, test the starter performance curve, adjust the starter gear ratio, so that the starter works in the area to the left of the maximum power point of the starter performance curve at low temperatures. At this time, the starter should drag the engine speed greater than 120r / min, and the starter power and transmission ratio selection is completed.

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