Engine rotation speed configuration circuit and construction machine

Abstract

The utility model discloses an engine rotating speed configuration circuit and engineering machinery, including ECM, rotating speed selection switch and power. Among them, ECM has two rotating speed selection pins, is used for the rotating speed of engine configuration when engine works in fixed rotating speed mode, and rotating speed selection switch has the input wiring terminal of external power supply and at least four can with input wiring terminal alternative communication's output gear end, and the first output gear end is not connected with ECM, and the second output gear end connects ECM's one rotating speed selection pin, and the third output gear end connects ECM's another rotating speed selection pin, and the fourth output gear end is connected with ECM's two rotating speed selection pins respectively through two diodes, and the utility model discloses only need to increase a small amount of external wiring and two diodes on the basis of existing circuit board can realize the scheme of low cost, especially suitable for application in the upgrading and reconstruction operation task of the internal hardware circuit of existing engineering machinery.

Description

Technical Field

[0001] This utility model belongs to the field of engineering machinery technology, and relates to the hardware circuit part of engineering machinery. Specifically, it is a speed configuration circuit designed for the engine of engineering machinery. Background Technology

[0002] ECM (Engine Control Module) is a module that works in conjunction with sensor networks and actuators to precisely regulate the engine. As the core of the engine control system, the ECM precisely controls key functions such as fuel injection, ignition timing, idle speed control, and emissions management, thereby ensuring efficient and stable engine operation under various operating conditions.

[0003] Idle speed is an engine operating state, including high idle speed and low idle speed. High idle speed is when the engine runs at a relatively high RPM (e.g., 1200 RPM) in neutral, commonly seen during cold starts or when the air conditioning is on. Low idle speed is when the engine runs at its lowest RPM (e.g., 600-800 RPM), the normal operating state after the engine has warmed up. The ECM (Electronic Control Module) precisely controls the engine idle speed by controlling actuators such as the idle air valve. In idle mode, the ECM ensures the engine maintains a stable RPM, preventing stalling or RPM fluctuations, thus improving engine smoothness and reliability.

[0004] Existing ECMs mainly consist of input circuits, output circuits, and a microprocessor. The microprocessor has only two digital speed selection pins, which, in conjunction with the speed selection switch, support up to three fixed speeds: low idle, high idle, and rated speed (e.g., 1500 rpm). However, some users also require the engine to operate at other fixed speeds to meet the specific speed requirements of certain devices.

[0005] To meet the specific needs of these users, circuit modifications to the ECM are required. Current modification solutions mainly include two approaches: one is to increase the number of speed selection pins on the microprocessor, but this leads to a shortage of interface resources for the microprocessor; the other is to add complex pin multiplexing circuitry to the periphery of the microprocessor, but this may require a complete redesign of the circuit board, resulting in high costs, long delivery cycles, and is unsuitable for upgrading existing construction machinery hardware circuits.

[0006] The information disclosed in this background section is only intended to enhance the understanding of the background technology of this application, and therefore may include prior art that is not known to those skilled in the art. Summary of the Invention

[0007] This utility model addresses at least one of the aforementioned technical problems in the background art by proposing an engine speed configuration circuit that can achieve additional configuration of a fixed engine speed at extremely low cost with only a small amount of external wiring.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: In one aspect, this utility model proposes an engine speed configuration circuit, comprising: ECM, which has two speed selection pins for configuring the engine speed when the engine is operating in fixed speed mode; A speed selection switch has an input terminal and at least four output positions, wherein the input terminal is selectively connected to one of the four output positions; wherein the first output position is not connected to the ECM, the second output position is connected to one of the speed selection pins of the ECM, the third output position is connected to another speed selection pin of the ECM, and the fourth output position is connected to the two speed selection pins of the ECM respectively through two diodes; A power supply, which is connected to the input terminal of the speed selection switch.

[0009] In some embodiments of this application, the anodes of the two diodes can be configured to be connected to the fourth output position of the speed selection switch, and the cathodes of the two diodes can be connected one-to-one with the two speed selection pins of the ECM, thereby enabling accurate configuration of the potential state of the two speed selection pins of the ECM.

[0010] In some embodiments of this application, the first output position of the speed selection switch can be configured to be suspended or in a high-resistance state to prevent the first output position from affecting the normal use of the power supply when connected to the input terminal.

[0011] In some embodiments of this application, the speed selection switch may be a rotary switch for ease of operation.

[0012] In some embodiments of this application, two digital input pins can be selected from the many input / output pins of the ECM as the speed selection pins, and four fixed speeds can be pre-set in the ECM to match the four level states that can be formed by combining the two speed selection pins. The ECM is configured to select one of the four pre-set fixed speeds according to the high and low level states of the two speed selection pins during actual use, thereby controlling the engine to run at the selected fixed speed.

[0013] In some embodiments of this application, the ECM has a power supply pin connected to a power supply; the power supply connected to the input terminal of the speed selection switch is configured to have the same potential as the power supply, thereby ensuring that the ECM can accurately identify the high and low level states of its two speed selection pins.

[0014] In some embodiments of this application, the power supply connected to the input terminal of the speed selection switch can be configured as a +5V DC power supply.

[0015] In another aspect, this utility model also proposes an engineering machine, including an engine, an ECM for controlling the engine speed, a speed selection switch, and a power supply; wherein, The ECM has two speed selection pins for configuring the engine speed when the engine is operating in a fixed speed mode; The speed selection switch has an input terminal and at least four output positions. The input terminal is selectively connected to one of the four output positions. Specifically, the first output position is not connected to the ECM, the second output position is connected to one of the speed selection pins of the ECM, the third output position is connected to another speed selection pin of the ECM, and the fourth output position is connected to the two speed selection pins of the ECM respectively through two diodes. The power supply is connected to the input terminal of the speed selection switch.

[0016] Compared with the prior art, the advantages and positive effects of this utility model are mainly reflected in: 1. This utility model starts from the existing circuit structure of the engine speed configuration circuit, makes full use of the idle position in its speed selection switch, and adds a diode between the idle position and the two speed selection pins of the ECM. This expands the number of fixed engine speed configurations from the existing maximum of three to four. This can meet the actual needs of some users who need to provide additional fixed engine speeds for their production machines, and help improve user satisfaction.

[0017] 2. The engine speed configuration circuit of this utility model has a simple structure and strong applicability. It can be implemented at low cost by adding a few wires and two diodes to the existing circuit board. It is especially suitable for upgrading the internal hardware circuit of existing construction machinery, with minimal increase in cost and short delivery cycle.

[0018] Other features and advantages of this utility model will become clearer after reading the detailed embodiments of this utility model in conjunction with the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0020] Figure 1 This is a circuit schematic diagram of one embodiment of an engine speed configuration circuit that supports up to three fixed speeds; Figure 2 This is a circuit diagram of one embodiment of the engine speed configuration circuit proposed in this utility model. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" or "linked" should be interpreted broadly, for example, it can refer to a direct connection, an indirect connection, or a connection within components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. In the description of the embodiments, specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0023] The terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature.

[0024] like Figure 1As shown, for an ECM with only two speed selection pins, Speed ​​Select1 and Speed ​​Select2, both of which are digital input pins, the existing circuit design uses the two output terminals S2 and S3 of the speed selection switch to connect one-to-one with the two speed selection pins Speed ​​Select1 and Speed ​​Select2 of the ECM. Simultaneously, the input terminal CON of the speed selection switch is configured to a high potential, for example, connected to the power supply VCC. Therefore, by changing the connection state between the input terminal CON and the two output terminals S2 and S3, the potential of the two speed selection pins Speed ​​Select1 and Speed ​​Select2 can be configured to exhibit three states: 00, 01, and 10; where 0 represents a low potential and 1 represents a high potential. By establishing a correspondence between each potential state and a fixed engine speed, the ECM can support three fixed speed selection configurations.

[0025] In order to enable the ECM to support four fixed speed selection configurations without changing the existing circuit board structure, this embodiment utilizes the idle output position of the existing speed selection switch, and with the help of a small number of external wiring harnesses and electronic components, the problem of additional configuration for fixed engine speeds can be solved at a very low cost without changing the ECM.

[0026] Specifically, such as Figure 2 As shown, this embodiment configures a speed selection switch with at least four output speed positions for the two-way switching pins SpeedSelect1 and SpeedSelect2 of the ECM. The speed selection switch has an input terminal CON, which can be selectively connected to one of the four output speed positions.

[0027] For the speed selection switch, its input terminal CON is configured to be connected to an external power supply VCC. The first output position terminal S1 is not connected to the two speed selection pins Speed ​​Select1 and Speed ​​Select2 of the ECM. Specifically, the first output position terminal S1 can be floated or configured to a high impedance state to avoid short-circuiting the power supply VCC or affecting the normal use of the power supply VCC by other circuits when the first output position terminal S1 is connected to the input terminal CON. The second output position terminal S2 is configured to be connected to one of the speed selection pins Speed ​​Select1 of the ECM, the third output position terminal S3 is connected to the other speed selection pin Speed ​​Select2 of the ECM, and the fourth output position terminal S4 is connected to the two speed selection pins Speed ​​Select1 and Speed ​​Select2 of the ECM one by one through two diodes VD1 and VD2 respectively.

[0028] Specifically, the anodes of the two diodes VD1 and VD2 can be connected to the fourth output position S4, the cathode of diode VD1 can be connected to the speed selection pin Speed ​​Select1 of the ECM, and the cathode of diode VD2 can be connected to the speed selection pin Speed ​​Select2 of the ECM.

[0029] In some embodiments, the speed selection switch can be a rotary switch, which allows users to switch speeds by turning it to facilitate operation.

[0030] The ECM requires a power supply to operate; specifically, the power supply VDD needs to be connected to the ECM's power pin Vbatt+. To enable the ECM to accurately identify the high and low levels of its two speed selection pins, Speed ​​Select1 and Speed ​​Select2, the voltage of the power supply VCC connected to the input terminal CON of the speed selection switch can be configured to be equal to the voltage of the power supply VDD, for example, both being +5V DC. Thus, when the ECM detects a voltage close to 5V on either Speed ​​Select1 or Speed ​​Select2, it can determine it as a high voltage (1); when it is significantly lower than 5V, it can determine it as a low voltage (0).

[0031] With the above circuit structure design, when the user rotates the speed selection switch to the first output position S1, the input terminal CON of the speed selection switch is connected to the first output position S1. Since the first output position S1 is not connected to the two speed selection pins Speed ​​Select1 and Speed ​​Select2 of the ECM, the potential state formed by the combination of the two speed selection pins Speed ​​Select1 and Speed ​​Select2 is 00.

[0032] When the user rotates the speed selection switch to the second output position S2, the input terminal CON of the speed selection switch is connected to the second output position S2, the diode VD1 is reverse cut off, the speed selection pin SpeedSelect1 of the ECM becomes high potential 1, and the speed selection pin SpeedSelect2 remains low potential 0. At this time, the potential state formed by the combination of the two speed selection pins SpeedSelect1 and SpeedSelect2 is 10.

[0033] When the user rotates the speed selection switch to the third output position S2, the input terminal CON of the speed selection switch is connected to the third output position S3, the diode VD2 is reverse cut off, the speed selection pin SpeedSelect1 of the ECM remains at a low potential of 0, and the speed selection pin SpeedSelect2 becomes a high potential of 1. At this time, the potential state formed by the combination of the two speed selection pins SpeedSelect1 and SpeedSelect2 is 01.

[0034] When the user rotates the speed selection switch to the fourth output position S4, the input terminal CON of the speed selection switch is connected to the fourth output position S4, and diodes VD1 and VD2 are turned on, causing both SpeedSelect1 and SpeedSelect2 pins of the ECM to become high potential 1. At this time, the potential state formed by the combination of the two speed selection pins SpeedSelect1 and SpeedSelect2 is 11.

[0035] Because this embodiment allows configuration of the ECM's two speed selection pins, Speed ​​Select1 and Speed ​​Select2, to form four potential states (00, 01, 10, and 11), four fixed speeds can be preset in the ECM, such as low idle speed (600 rpm), high idle speed (1200 rpm), rated speed (1500 rpm), and a fixed speed of 1800 rpm required by other equipment. A one-to-one correspondence is established between these four fixed speeds and the four potential states (00, 01, 10, and 11) formed by the combination of the two speed selection pins, Speed ​​Select1 and Speed ​​Select2. In actual use, the ECM can control the engine to operate at the corresponding fixed speed according to the speed selection switch selected by the user.

[0036] Industrial applicability

[0037] When the engine speed configuration circuit of this embodiment is applied to construction machinery, such as excavators and cranes, it can select and configure a fixed speed for the engine in the construction machinery.

[0038] Specifically, when the user needs the engine to run at a fixed speed, the engine is controlled to enter a fixed-speed operation mode. The speed selection switch is switched to the appropriate position to configure the potential states of the two speed selection pins, Speed ​​Select1 and Speed ​​Select2, of the ECM in the construction machinery. The ECM determines the corresponding fixed speed based on the potential states of its two speed selection pins, Speed ​​Select1 and Speed ​​Select2. Subsequently, the ECM receives signals from sensors such as the crankshaft position sensor, throttle position sensor, and air flow meter in real time to obtain parameters such as actual engine speed and intake air volume. The ECM compares the actual engine speed with the target speed (the fixed speed selected by the user) and dynamically adjusts the fuel injection quantity and ignition timing to stabilize the actual engine speed at the target speed, allowing the engine to operate at the user-selected fixed speed to meet the user's needs.

[0039] Of course, the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by this utility model.

Claims

1. An engine speed configuration circuit, characterized in that, include: ECM, which has two speed selection pins for configuring the engine speed when the engine is operating in fixed speed mode; A speed selection switch has an input terminal and at least four output positions, wherein the input terminal is selectively connected to one of the four output positions; wherein the first output position is not connected to the ECM, the second output position is connected to one of the speed selection pins of the ECM, the third output position is connected to another speed selection pin of the ECM, and the fourth output position is connected to the two speed selection pins of the ECM respectively through two diodes; A power supply, which is connected to the input terminal of the speed selection switch.

2. The engine speed configuration circuit according to claim 1, characterized in that, The anodes of the two diodes are connected to the fourth output position of the speed selection switch, and the cathodes of the two diodes are respectively connected to the two speed selection pins of the ECM.

3. The engine speed configuration circuit according to claim 1, characterized in that, The first output position of the speed selection switch is suspended or configured in a high-resistance state.

4. The engine speed configuration circuit according to claim 1, characterized in that, The speed selection switch is a rotary switch.

5. The engine speed configuration circuit according to any one of claims 1 to 4, characterized in that, The two speed selection pins are digital input pins. The ECM selects one of four preset fixed speeds based on the high and low level states of the two speed selection pins and controls the engine to run at the selected fixed speed.

6. The engine speed configuration circuit according to claim 5, characterized in that, The ECM has a power supply pin, which is connected to a power supply. The power supply connected to the input terminal of the speed selection switch has the same potential as the power supply.

7. The engine speed configuration circuit according to claim 6, characterized in that, The power supply connected to the input terminal of the speed selection switch is a +5V DC power supply.

8. An engineering machinery, characterized in that, It includes an engine and an engine speed configuration circuit as described in any one of claims 1 to 7; wherein the ECM is used to control the engine speed.

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