Cutting knife detection device of mower

Abstract

The utility model relates to the technical field of mowers, in particular to a cutting knife detection device of a mower, which can realize detection of motor load and comprises a cutting knife connected with a mowing motor, the mowing motor is connected with a height screw rod, one end of the height screw rod is connected with a lifting motor through a transmission gear, the mowing motor is connected with a single chip microcomputer U4 through a driving circuit, and the single chip microcomputer U4 is connected with a power supply. The single chip microcomputer U4 is connected with a load current detection circuit, the load current detection circuit comprises a current amplifier U3, a pin 6 of the current amplifier U3 is connected with one end of a resistor R1, the other end of the resistor R1 is connected with one end of a capacitor C3 and a pin 11 of the single chip microcomputer U4, a pin 5 of the current amplifier U3 is grounded, a pin 4 of the current amplifier U3 is connected with a mowing motor, and a pin 3 of the current amplifier U3 is connected with one end of a resistor R2, one end of a capacitor C2 and a 3.3 V power supply. A pin 1 of the current amplifier U3 is connected with one end of a capacitor C4, a reference electrode and a negative electrode of the voltage stabilizing source U2, the other end of the resistor R2, a pin 2 of the current amplifier U3 is connected with the other end of the capacitor C2, and the other end of the capacitor C4 and a positive electrode of the voltage stabilizing source U2 are grounded.

Description

Technical Field

[0001] The utility model relates to the technical field of lawn mowers, in particular to a cutting blade detection device for lawn mowers. Background Art

[0002] Lawn mowers play a very important role in lawn trimming, which can greatly reduce the intensity of human labor. The cutting blade of a traditional lawn mower is set at a fixed height, and the cutting height is also fixed. If the grass is high and the cutting blade is placed low, the cut grass will be longer, and the wind will blow it everywhere. Cutting long grass not only increases the burden on the motor, but also aggravates the wear of the cutting blade. Therefore, the current smart lawn mower can adjust the height of the cutting blade to reduce the burden on the motor. The current height adjustment is achieved by using a height screw and a lifting motor, but the load of the cutting blade motor corresponding to the actual cutting blade cannot be understood. If the height is not adjusted in place, it will still cause the motor load to be too high, causing damage due to long-term operation. Summary of the invention

[0003] In order to solve the problem that the load of the existing cutter motor cannot be detected, the utility model provides a cutter detection device for a lawn mower, which can realize the detection of the motor load.

[0004] The technical scheme is as follows: a mower blade detection device, comprising a mower blade connected to a mowing motor, the mowing motor connected to a height screw, one end of the height screw connected to a lifting motor through a transmission gear, characterized in that the mowing motor is connected to a single-chip microcomputer U4 through a drive circuit, the model is STM32F103C8T6, the single-chip microcomputer U4 is connected to a load current detection circuit, the load current detection circuit includes a current amplifier U3, model INA199A2, and the 6th pin of the current amplifier U3 is connected to a resistor R1 One end, the other end of the resistor R1 is connected to one end of the capacitor C3 and the 11th pin of the single-chip computer U4, the 5th pin of the current amplifier U3 is grounded, and the 4th pin is connected to the mowing motor, the 3rd pin of the current amplifier U3 is connected to one end of the resistor R2, one end of the capacitor C2, and a 3.3V power supply, the 1st pin of the current amplifier U3 is connected to one end of the capacitor C4, the reference electrode and the negative electrode of the voltage regulator U2, and the other end of the resistor R2, the 2nd pin of the current amplifier U3 is connected to the other end of the capacitor C2, the other end of the capacitor C4, and the positive electrode of the voltage regulator U2 are all grounded.

[0005] Its further feature is that the drive circuit is a three-phase drive circuit, including three bridge drive chips, three dual-core MOS tubes, three operational amplifiers, and a motor connector.

[0006] After adopting the utility model, a load current detection circuit is added, and the running current of the mowing motor can be collected by using the current amplifier U3 to realize the detection of the motor load. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a schematic diagram of the internal mechanical structure of the lawn mower of the utility model;

[0008] Figure 2 This is a schematic diagram of the circuit control of the utility model (omitting the power supply circuit);

[0009] Figure 3 This is the schematic diagram of the microcontroller circuit;

[0010] Figure 4 This is the schematic diagram of the load current detection circuit;

[0011] Figure 5 This is the driving circuit schematic diagram of the lawn mowing motor;

[0012] Figure 6 This is the schematic diagram of the power supply circuit;

[0013] Figure 7 The driving circuit schematic diagram of the lifting motor;

[0014] Figure 8 This is the schematic diagram of the infrared distance sensor and Hall sensor circuit. DETAILED DESCRIPTION

[0015] See Figures 1 to 8 As shown, a mower blade detection device includes a mower blade 13 connected to a mower blade motor 3. The mower blade motor 3 is installed in a motor housing 2. The motor housing 2 is connected to a height screw rod 4. One end of the height screw rod 4 is connected to a lifting motor 11 through a transmission gear 12. The lifting motor 11 drives the height screw rod 4 to rotate, so that the mower blade motor 3 can be lifted and lowered, thereby driving the mower blade 13 to be lifted and lowered. 8 in the figure is a control board. The control board is provided with a driving circuit of the mower blade motor, a driving circuit of the lifting motor, and a load current detection circuit. The mower blade motor 3 is connected to a single-chip microcomputer U4 through the driving circuit. The single-chip microcomputer U4 is connected to a load current detection circuit. The load current detection circuit includes a current amplifier U3, model INA199A2, pin 6 of the current amplifier U3 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the capacitor C3 and pin 11 of the microcontroller U4, pin 5 of the current amplifier U3 is grounded, pin 4 is connected to the lawn mowing motor, pin 3 of the current amplifier U3 is connected to one end of the resistor R2, one end of the capacitor C2, and a 3.3V power supply, pin 1 of the current amplifier U3 is connected to one end of the capacitor C4, the reference electrode and negative electrode of the voltage regulator U2, and the other end of the resistor R2, and pin 2 of the current amplifier U3 is connected to the other end of the capacitor C2, the other end of the capacitor C4, and the positive electrode of the voltage regulator U2 are all grounded.

[0016] The load current detection circuit can collect the current load current changes of the lawn mower motor. The above information can be subsequently processed. The subsequent processing is not within the scope of this utility model patent. This utility model only provides a device that can detect the load current.

[0017] The driving circuit of the lawn mower motor is a three-phase driving circuit, including three bridge driving chips, three dual-core MOS tubes, and three operational amplifiers, corresponding to the U phase, V phase, and W phase respectively. The specific circuit principle is shown in the figure. The motor connector H1 is connected to the lawn mower motor.

[0018] In addition, the driving circuit schematic diagram of the lifting motor is also given, which is a single-phase motor.

[0019] The power circuit provides power to the entire system.

[0020] The Hall sensor 10 is used to sense the magnet 6. The combination can be used for distance calibration. Each time the device is turned on, the distance of the current infrared distance sensor 9 needs to be calibrated. The infrared distance sensor 9 is used in conjunction with the distance baffle 5. The Hall sensor 10 and the infrared distance sensor 9 are both connected to the single chip computer U4. Figure 1 The number 7 in the middle is the data line connected to the main control chip.

Claims

1. A mower blade detection device, comprising a mower blade connected to a mowing motor, wherein the mowing motor is connected to a height screw, and one end of the height screw is connected to a lifting motor through a transmission gear, wherein: The lawn mowing motor is connected to a single-chip microcomputer U4 through a drive circuit, model STM32F103C8T6, and the single-chip microcomputer U4 is connected to a load current detection circuit, and the load current detection circuit includes a current amplifier U3, model INA199A2, and the 6th pin of the current amplifier U3 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to one end of the capacitor C3 and the 11th pin of the single-chip microcomputer U4, and the 5th pin of the current amplifier U3 is grounded, and the 4th pin is connected to the lawn mowing motor, and the 3rd pin of the current amplifier U3 is connected to one end of the resistor R2, one end of the capacitor C2, and a 3.3V power supply, and the 1st pin of the current amplifier U3 is connected to one end of the capacitor C4, the reference electrode and the negative electrode of the voltage stabilizing source U2, and the other end of the resistor R2, and the 2nd pin of the current amplifier U3 is connected to the other end of the capacitor C2, the other end of the capacitor C4, and the positive electrode of the voltage stabilizing source U2 are all grounded.

2. A lawn mower blade detection device according to claim 1, characterized in that: The driving circuit is a three-phase driving circuit, including three bridge driving chips, three dual-core MOS tubes, three operational amplifiers, and a motor connector.

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