Starter controlled by secondary voltage system

Abstract

The utility model relates to the technical field of starters, and discloses a starter controlled by a secondary voltage system, which comprises an ECU (Electronic Control Unit), a key switch, a storage battery, a DC / DC (Direct Current / Direct Current) power converter, an auxiliary starting relay and a starter assembly, the auxiliary starting relay and the ECU control unit are connected to the output end of the DC / DC power converter in parallel, the starter assembly comprises a starting relay component, a first starting coil terminal of the starting relay component is connected with the ECU control unit and the auxiliary starting relay, and a second starting coil terminal of the starting relay component is connected with the ECU control unit. According to the utility model, 12V power supply voltage is converted into 24V voltage to supply power to the ECU, a 24V starting relay coil is supplied with power by an auxiliary relay contact and is connected to the ECU, and the ECU controls the starter, so that the control and protection strategy implementation of the starter by the ECU is realized, the conditions of on-load, long-time dragging and reverse dragging of the starter are avoided, and the fault rate of the starter is further reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of starters, in particular to a starter controlled by a secondary voltage system. Background Art

[0002] Generally, the voltage system of commercial diesel engines is 24V. As the application scope of engines continues to expand, the engines need to be matched to vehicles that use a 12V voltage system, such as agricultural machinery. A vehicle engine has two voltage systems for application.

[0003] In order to meet the needs of the vehicle's 12V voltage system, some engine manufacturers adopt the technical route of developing the working voltage of the engine's electrical system, which requires the redevelopment and design of multiple components on the engine, such as the electronic control unit ECU, injector, high-pressure pump, various sensors, starter, generator, etc., so that the components on the engine form a 12V voltage system consistent with the vehicle. This method has a long development cycle and high development costs, especially for the electronic control unit ECU. Some engine manufacturers' ECUs still use a 24V system, while the starter, generator, auxiliary preheating, etc., which are closely related to the vehicle's power supply, remain consistent with the vehicle's 12V voltage system.

[0004] See also Figure 1 , Figure 1 The diagram shows a starter control circuit diagram of a certain vehicle model, including relay component 1, electromagnetic switch 2, motor 3, engine control unit ECU 4, start key switch 5, battery 6 and DC / DC power converter 7. When the engine is started, the start gear of key switch 5 is turned on, the coil of relay component 1 is energized, contacts 1.1 and 1.2 are connected, 2.1 end of electromagnetic switch 2 is energized, 2.21 attracts coil L1 and 2.22 keeps coil L2 energized, 3.1 of motor 3 is energized, current passes through the stator and rotor, and the engine is started. This is the normal starter control working process, and the DC / DC voltage converter supplies power to the engine control system.

[0005] Since the engine ECU control unit 4 is a 24V system and the starter is a 12V system, the voltage drop of the relay component 1 is very large when the engine is started, especially under low temperature and other working conditions, when the system voltage drops, the 1.2 voltage level of the relay component 1 is different and cannot be connected to the ECU control unit 4. In this case, the starter and the engine control unit are isolated, and the engine loses control of the starter, and thus cannot control the work of the starter. The starter is very easy to be damaged under load, long-term dragging and reverse dragging, causing the engine to fail to start, causing customer complaints. Moreover, the cost of the starter for diesel engines, especially large-displacement diesel engines, is high, and accidental damage causes economic losses to customers and engine manufacturers. Utility Model Content

[0006] The technical problem to be solved by the utility model is that when the voltage of the existing starter is different from that of the ECU, the starter cannot be connected to the ECU, and thus the starter cannot be controlled by the ECU.

[0007] In order to solve the above technical problems, the technical solution of the utility model is to provide a starter controlled by a secondary voltage system, including an ECU control unit, a key switch, a battery, a DC / DC power converter, an auxiliary starting relay and a starter assembly, wherein the positive electrode of the battery is respectively connected to the input end of the DC / DC power converter, the starter assembly and the key switch, the key switch is respectively connected to the ECU control unit and the auxiliary starting relay, the auxiliary starting relay and the ECU control unit are connected in parallel at the output end of the DC / DC power converter, the starter assembly includes a starting relay component, the starting relay component includes a first starting coil terminal and a second starting coil terminal, the first starting coil terminal is respectively connected to the ECU control unit and the auxiliary starting relay, and the second starting coil terminal is connected to the ECU control unit.

[0008] Optionally, the starter assembly further includes an electromagnetic switch and a motor, wherein the electromagnetic switch is connected to the positive electrode of the battery, the motor and a starter relay component, and the motor is grounded.

[0009] Optionally, the rated working voltage of the internal coil of the starter relay component is 24V, the current passing through is less than 1.5A at the rated voltage, and the electromagnetic switch and the motor adopt a 12V system voltage.

[0010] Optionally, the starter relay component and the electromagnetic switch are arranged on the housing or the front cover of the motor.

[0011] Optionally, the negative pole of the battery is grounded, and the ground terminal of the DC / DC power converter is connected to the ECU control unit and grounded.

[0012] Optionally, the rated operating voltage of the ECU control unit is 24V, and the rated voltage of the battery is 12V.

[0013] Optionally, the key switch includes an input terminal, a power-on gear interface on the ECU and a start gear terminal, the auxiliary starting relay is provided with a first auxiliary coil terminal and a second auxiliary coil terminal, the input terminal is connected to the positive pole of the battery, the power-on gear interface on the ECU is connected to the ECU control unit, the start gear terminal is connected to the first auxiliary coil terminal, and the second auxiliary coil terminal is grounded.

[0014] Optionally, the rated operating voltage of the coil of the auxiliary starting relay is 12V, and the rated load current of the auxiliary starting relay is less than 5A.

[0015] In summary, the utility model has at least one of the following beneficial effects:

[0016] 1. The starting system control scheme of the utility model is aimed at 12V applications with relatively small market demand. The voltage of the 12V battery is converted into 24V voltage through a voltage converter to power the ECU. The 12V auxiliary relay coil is directly controlled by the starting system key switch. The 12V power supply supplies power to the 24V starting relay coil through the auxiliary relay contacts. The control end of the 24V relay coil is connected to the ECU, and the ECU controls the starting and stopping of the starter. There is no need to develop a new ECU voltage system. The control of the starter is connected to the ECU, so that the ECU can control the starter and implement the protection strategy, avoiding the starter under load, long-term dragging and reverse dragging, thereby reducing the failure rate of high-value starters.

[0017] 2. The starter controlled by the secondary voltage system of the utility model is composed of an integral starter assembly including a motor, a starter relay component arranged on the front cover of the motor, an electromagnetic switch arranged on the front cover of the motor, and a plurality of screws for fixing and connecting. It is only necessary to fix the starter body according to the general assembly process of the starter, and the assembly process is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the connection between the existing 24V ECU control unit and the starter;

[0019] Figure 2 This is a connection diagram of the secondary voltage system of the utility model;

[0020] Figure 3 This is a schematic diagram of the installation position of the starter assembly of the utility model;

[0021] Figure 4 This is a schematic side view of the installation of the starter assembly of the utility model;

[0022] In the figure: 1. Relay component; 1.1. First starting coil terminal; 1.2. Second starting coil terminal; 1.3. Starting input terminal; 1.4. Starting output terminal; 2. Electromagnetic switch; 2.1 Coil common terminal; 2.2.1 Pick-up coil terminal; 2.2.2. Maintaining coil terminal; 2.3. Electromagnetic input contact; 2.4. Electromagnetic output contact; 3. Motor; 3.1. Stator power supply; 3.2. Negative terminal of motor; 4. ECU control unit; 4.1. First connection terminal; 4.2. Second connection terminal; 4.3. Third connection terminal; 4.4. Fourth connection terminal ;4.5, the fifth connection terminal;5, key switch;5.1, input terminal;5.2, ECU power-on gear interface;5.3, start gear terminal;6, battery;6.1, positive terminal;6.2, negative terminal;7, DC / DC power converter;7.1, input terminal;7.2, ground terminal;7.3, output terminal;8, auxiliary starting relay;8.1, first auxiliary coil terminal;8.2, second auxiliary coil terminal;8.3, auxiliary input terminal;8.4, auxiliary output terminal;9, starter assembly;L1, pull-in coil;L2, holding coil. DETAILED DESCRIPTION

[0023] The utility model discloses a starter controlled by a two-level voltage system, referring to Figure 2 , including an ECU control unit 4, a key switch 5, a battery 6, a DC / DC power converter 7, an auxiliary starting relay 8 and a starter assembly 9, wherein the positive electrode of the battery 6 is respectively connected to the input terminal 7.1 of the DC / DC power converter 7, the starter assembly 9 and the key switch 5, the key switch 5 is respectively connected to the ECU control unit 4 and the auxiliary starting relay 8, the auxiliary starting relay 8 and the ECU control unit 4 are connected in parallel to the output terminal 7.3 of the DC / DC power converter 7, the starter assembly 9 includes a starting relay component 1, an electromagnetic switch 2 and a motor 3, the electromagnetic switch 2 is connected to the positive electrode of the battery 6, the motor 3 and the starting relay component 1, the motor 3 is grounded, the starting relay component 1 includes a first starting coil terminal 1.1 and a second starting coil terminal 1.2, the first starting coil terminal 1.1 is respectively connected to the ECU control unit 4 and the auxiliary starting relay 8, and the second starting coil terminal 1.2 is connected to the ECU control unit 4.

[0024] Specifically, the positive terminal 6.1 of the positive pole of the battery 6 is respectively connected to the input terminal 7.1 of the DC / DC power converter 7, the electromagnetic input contact 2.3 of the electromagnetic switch 2 and the input terminal 5.1 of the key switch 5, the negative terminal 6.2 of the negative pole of the battery 6 is grounded, the ECU power-on gear interface 5.2 of the key switch 5 is connected to the first connection terminal 4.1 of the ECU control unit 4, the start gear terminal 5.3 of the key switch 5 is connected to the first auxiliary coil terminal 8.1 of the auxiliary starting relay 8, the second auxiliary coil terminal 8.2 of the auxiliary starting relay 8 is grounded, the auxiliary input terminal 8.3 of the auxiliary starting relay 8 and the second connection terminal 4.2 of the ECU control unit 4 are connected in parallel to the output terminal 7.3 of the DC / DC power converter 7, and the ground terminal 7.2 of the DC / DC power converter 7 is connected to the third connection terminal 4.3 of the ECU control unit 4 and is grounded;

[0025] In the starter assembly 9, the first starting coil terminal 1.1 of the starting relay component 1 is connected to the fourth connection terminal 4.4 of the ECU control unit 4 and the auxiliary output terminal 8.4 of the auxiliary starting relay 8 respectively, the second starting coil terminal 1.2 is connected to the fifth connection terminal 4.5 of the ECU control unit 4, the starting input terminal 1.3 of the starting relay component 1 is connected to the electromagnetic input contact 2.3 of the electromagnetic switch 2, the starting output terminal 1.4 of the starting relay component 1 is connected to the coil common terminal 2.1 of the pull-in coil L1 and the holding coil L2 of the electromagnetic switch 2, the electromagnetic output contact 2.4 of the electromagnetic switch 2 is connected to the pull-in coil terminal 2.21 of the pull-in coil L1 and the stator power supply 3.1 of the motor 3, and the holding coil terminal 2.22 of the holding coil L2 of the electromagnetic switch 2 and the motor negative terminal 3.2 of the negative pole of the motor 3 are grounded.

[0026] Example

[0027] In this embodiment, the voltage of the battery 6 is 12V, the rated working voltage of the ECU control unit 4 is 24V, the input voltage of the input terminal 7.1 of the DC / DC power converter 7 is 12V, and the output voltage of the output terminal 7.3 of the DC / DC power converter 7 is 24V;

[0028] The rated working voltage of the coil of the auxiliary starting relay 8 is 12V, and the rated load current of the auxiliary starting relay 8 is less than 5A;

[0029] The rated working voltage of the internal coil of the starter relay component 1 is 24V, and the current passing through it at the rated voltage is less than 1.5A. The contact current of the starter relay component 1 is 300A, and the load capacity meets the current of the pull-in coil L1 and the holding coil L2 of the starter 12V electromagnetic switch 2. The working voltage of the electromagnetic switch 2 and the motor 3 is 12V. Figure 3 and Figure 4The starting relay component 1 and the electromagnetic switch 2 are installed on the housing or front cover of the motor 3.

[0030] The starting process of this embodiment is as follows: the engine starts in the initial state before starting, the voltage of the input terminal 7.1 of the DC / DC power converter 7, the input terminal 5.1 of the key switch 5, the electromagnetic input contact 2.3 of the electromagnetic switch 2 and the starting input terminal 1.3 of the starting relay component 1 is 12V. When starting, the key switch 5 is rotated to the ECU power-on gear interface 5.2, the whole vehicle is powered on and remains connected, and the ECU control unit 4 receives the whole vehicle power-on signal. At the same time, the output terminal 7.3 of the DC / DC power converter 7 outputs a 24V voltage, and supplies 24V voltage to the power supply module of the ECU control unit 4 and the auxiliary input terminal 8.3 of the auxiliary relay. When the key switch 5 is rotated to the start gear terminal 5.3, the first auxiliary coil terminal 8.1 of the auxiliary starting relay 8 is energized, the contact is closed, and the auxiliary output terminal 8.4 of the auxiliary starting relay 8 is powered on. The first starting coil terminal 1.1 of the starting relay component 1 is energized, and the second starting coil terminal 1.2 enters the fifth connection terminal 4.5 of the ECU control unit 4, and determines whether the engine starting conditions are met according to other input signals of the vehicle. If so, the pin of the fifth connection terminal 4.5 is pulled down to ground, the coil of the starting relay component 1 is energized, the contacts are closed, the starting output terminal 1.4 is energized, the electromagnetic switch 2 obtains a 12V working voltage, the attraction coil L1 and the holding coil L2 are energized to the negative terminal 3.2 of the motor 3, and under the action of the electromagnetic force generated by the attraction coil L1 and the holding coil L2, the one-way device and the driving gear are pulled out to mesh with the flywheel gear ring, the contacts of the electromagnetic switch 2 are closed, and a large current passes through the motor 3, and the starter starts to crank the engine.

[0031] The ECU control unit 4 can monitor the engine speed, battery 6 voltage, neutral switch and other information, and then implement various protections for the starter to reduce the failure of the starter; if the neutral signal and / or the engine speed is 0RPM, the coil in the starter relay component 1 is allowed to be energized, and the starter works to start the engine;

[0032] When the starter is starting the engine, when it detects that the engine speed has reached the idle speed, such as 500RPM, that is, the engine has started, the ECU control unit 4 disconnects the current in the coil of the starter relay component 1, which can stop the starter from working to prevent the one-way device and armature failure caused by the starter overrunning for a long time.

[0033] The starter of the utility model is an integral combined starter assembly composed of a starter relay component 1, an electromagnetic switch 2, and a motor 3. Compared with the existing technology, the 24V starter relay component 1 is assembled on the front cover of the 12V motor 3, and the starter assembly 9 is an integrated combined component. The connection of the wiring harness is integrated in the starter assembly, and the assembly process remains unchanged; the utility model uses the 12V power supply of the vehicle starting system control solution to power the coil of the 24V starter relay component 1 through the auxiliary starting relay 8, and the coil control end of the 24V starter relay component 1 is connected to the ECU, and the ECU controls the starting and stopping of the starter, ensuring that the engine using the 24V electronic control system is matched and applied to the whole vehicle with a 12V voltage system quickly, at low development cost and with high reliability, without the need for the development of a new ECU voltage system, and realizes the control and protection strategy implementation of the starter by the ECU, avoiding the starter under load, long-term dragging and reverse dragging, thereby reducing the failure rate of high-value starters.

[0034] The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, those skilled in the art should understand that any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A starter controlled by a two-stage voltage system, characterized in that: The invention comprises an ECU control unit (4), a key switch (5), a storage battery (6), a DC / DC power converter (7), an auxiliary starting relay (8) and a starter assembly (9); the positive electrode of the storage battery (6) is respectively connected to an input end (7.1) of the DC / DC power converter (7), the starter assembly (9) and the key switch (5); the key switch (5) is respectively connected to the ECU control unit (4) and the auxiliary starting relay (8); the auxiliary starting relay (8) and the ECU control unit (4) are connected in parallel to an output end (7.3) of the DC / DC power converter (7); the starter assembly (9) comprises a starting relay component (1); the starting relay component (1) comprises a first starting coil terminal (1.1) and a second starting coil terminal (1.2); the first starting coil terminal (1.1) is respectively connected to the ECU control unit (4) and the auxiliary starting relay (8); the second starting coil terminal (1.2) is connected to the ECU control unit (4).

2. The starter controlled by the two-stage voltage system according to claim 1, characterized in that: The starter assembly (9) further comprises an electromagnetic switch (2) and a motor (3); the electromagnetic switch (2) is connected to the positive pole of the battery (6), the motor (3) and the starter relay component (1); and the motor (3) is grounded.

3. The starter controlled by the two-level voltage system according to claim 2, characterized in that: The rated working voltage of the internal coil of the starter relay component (1) is 24V, the current flowing through it at the rated voltage is less than 1.5A, and the electromagnetic switch (2) and the motor (3) adopt a 12V system voltage.

4. The starter controlled by the two-level voltage system according to claim 3, characterized in that: The starting relay component (1) and the electromagnetic switch (2) are arranged on the housing or the front cover of the motor (3).

5. The starter controlled by the two-level voltage system according to claim 1, characterized in that: The negative pole of the battery (6) is grounded, and the grounding terminal (7.2) of the DC / DC power converter (7) is connected to the ECU control unit (4) and is grounded.

6. The starter controlled by the two-level voltage system according to claim 5, characterized in that: The rated working voltage of the ECU control unit (4) is 24V, and the rated voltage of the battery (6) is 12V.

7. The starter controlled by the two-level voltage system according to claim 1, characterized in that: The key switch (5) comprises an input terminal (5.1), an ECU power-on interface (5.2) and a start-up terminal (5.3); a first auxiliary coil terminal (8.1) and a second auxiliary coil terminal (8.2) are provided on the auxiliary start relay (8); the input terminal (5.1) is connected to the positive pole of the battery (6); the ECU power-on interface (5.2) is connected to the ECU control unit (4); the start-up terminal (5.3) is connected to the first auxiliary coil terminal (8.1); and the second auxiliary coil terminal (8.2) is grounded.

8. The starter controlled by the two-level voltage system according to claim 7, characterized in that: The rated working voltage of the coil of the auxiliary starting relay (8) is 12V, and the rated load current of the auxiliary starting relay (8) is less than 5A.

Images