Signal converter

A signal converter, including: a power circuit, a microprocessor, a plurality of input signal interface circuits, a first multiplexer switch, and an output signal interface circuit. The power circuit supplies power for each circuit of the signal converter. The plurality of input signal interface circuits is disposed side by side, and in operation, one of the plurality of input signal interface circuits is connected to the first multiplexer switch to work. The plurality of input signal interface circuits includes input terminals and output terminals. The input terminals receive corresponding input signals, and the output terminals are connected to the microprocessor. The microprocessor includes an output terminal which is connected to the output signal interface circuit. The microprocessor controls the first multiplexer switch to connect to one of the plurality of input signal interface circuits.

BACKGROUND

This disclosure relates to a signal converter for electronically commutated motors (ECMs).

ECMs, also known as Brushless DC electric motors (BLDC motors), are used in direct drive fans in HVAC equipment; they are efficient and have a variety of speed controls to choose from.

As shown inFIGS. 2-4, a conventional ECM includes a main body1and a motor controller2. The main body1includes a housing11, a stator assembly12and a rotor assembly13. The motor controller2includes a control box22and a control circuit board21mounted in the control box22. The control box22is mounted in the tail of the housing11. The control circuit board21includes a power supply circuit, a microprocessor MCU, an IGBT (Insulated Gate Bipolar Transistor) inverter circuit, an operating parameter detection unit, and an interface signal processing circuit.

During operation, the motor controller requires that the motor is matched to the control system of specific electrical equipment. This is because different control systems must match different control signals.

Conventionally, for each kind of control signal and for each kind of control system, a specific ECM and corresponding motor controller are developed. This keeps the development and production costs high.

SUMMARY

Disclosed is a signal converter for electronically commutated motors (ECMs). The signal converter can enable the electronically commutated motors to adapt to the control signals of various electrical equipment and/or various control signals of one electrical equipment. This facilitates the management and application of the motors.

Disclosed is a signal converter for connecting electrical equipment and an ECM, the signal converter being configured to convert the control signal from the electrical equipment into an input signal recognizable to the ECM. The signal converter comprises: a power circuit, a microprocessor, a plurality of input signal interface circuits, a first multiplexer switch, and an output signal interface circuit; the power circuit supplies power for each circuit of the signal converter; the plurality of input signal interface circuits is disposed side by side, and in operation, one of the plurality of input signal interface circuits is connected to the first multiplexer switch to work; the plurality of input signal interface circuits comprises input terminals and output terminals; the input terminals receive corresponding input signals, and the output terminals are connected to the microprocessor; the microprocessor comprises an output terminal which is connected to the output signal interface circuit; and the microprocessor controls the first multiplexer switch to connect to one of the plurality of input signal interface circuits.

The microprocessor can comprise a Bluetooth module; an external mobile equipment sends instructions to the microprocessor via the Bluetooth module, and the microprocessor controls the first multiplexer switch to select one of the plurality of input signal interface circuits to work according to the instructions.

The microprocessor can comprise a serial communication circuit; an external equipment sends instructions to the microprocessor via the serial communication circuit, and the microprocessor controls the first multiplexer switch to select one of the plurality of input signal interface circuits to work according to the instructions.

The signal converter can further comprise a rotary switch or button; instructions are sent to the microprocessor via the rotary switch or button, and the microprocessor controls the first multiplexer switch to select one of the plurality of input signal interface circuits to work according to the instructions.

The signal converter can further comprise an input signal status indicator, a power status indicator, and an output signal status indicator.

The input signals can comprise 0-10 VDC signals, pulse-width modulation (PWM) signals, 4-20 mA signals, serial communication signals, line voltage switching signals and 24 V temperature control switching signals; the serial communication signals are corresponding to communication protocols, and the signal converter supports multiple serial communication signal inputs with different communication protocols.

The power circuit can comprise a plurality of power input interface circuits and a second multiplexer switch; the plurality of power input interface circuits is disposed side by side; input terminals of the plurality of power input interface circuits are connected to corresponding input powers, and output terminals of the plurality of power input interface circuits are connected to the second multiplexer switch; in operation, the microprocessor controls the second multiplexer switch to select one of the plurality of power input interface circuits to work.

The input powers can comprise +5 VDC USB power supply, between +12 VDC and +24 VDC input power, and dry battery DC power supply.

A plurality of output signal interface circuits can be disposed side by side; the plurality of output signal interface circuits is connected to a third multiplexer switch; the microprocessor controls the third multiplexer switch to select one of the plurality of output signal interface circuits to output a corresponding output signal via an output terminal of the plurality of output signal interface circuits.

The output signal can comprise a 0-10 VDC signal, pulse-width modulation (PWM) signal, 4-20 mA signal, serial communication signal, line voltage switching signal and 24 V temperature control switching signal.

The power circuit can supply +24 VDC or +12 VDC power to a system controller or potentiometer of a user side.

Advantages of the signal converter for electronically commutated motors (ECMs) as described in the disclosure are summarized as follows:

1. The signal converter can enable the electronically commutated motors to adapt to the control signals of different electrical equipment or different control signals of one electrical equipment, thus facilitating the management and application of the motors.

2. The arrangement of the Bluetooth module and the serial communication circuit simplifies the selection of the first multiplexer switch for one of the plurality of input signal interface circuits.

3. The input signal status indicator, the power status indicator, and the output signal status indicator can directly indicate whether the input signals, the power supply and the output signals are correct or not.

4. The input powers comprise +5 VDC USB power supply, between +12 VDC and +24 VDC input power, and dry battery DC power supply, meeting different input power requirements.

5. The plurality of output signal interface circuits is corresponding to different output signals, which expands the application scope of the ECMs.

DETAILED DESCRIPTION

To further illustrate, embodiments detailing a signal converter are described below. It should be noted that the following embodiments are intended to describe and not to limit the disclosure.

As shown inFIGS. 5-9, provided is a signal converter for electronically commutated motors (ECMs). The signal converter is disposed between an electrical equipment (such as a system controller of heating, ventilating and air conditioning (HVAC) and an ECM. The signal converter can convert the control signal from the electrical equipment into an input signal recognizable to the ECM. The signal converter comprises: a power circuit, a microprocessor, a plurality of input signal interface circuits, a first multiplexer switch, and an output signal interface circuit; the power circuit supplies power for each circuit of the signal converter; the plurality of input signal interface circuits is disposed side by side, and in operation, one of the plurality of input signal interface circuits is connected to the first multiplexer switch to work; the plurality of input signal interface circuits comprises input terminals and output terminals; the input terminals receive corresponding input signals, and the output terminals are connected to the microprocessor; the microprocessor comprises an output terminal which is connected to the output signal interface circuit; and the microprocessor controls the first multiplexer switch to connect to one of the plurality of input signal interface circuits.

The microprocessor can comprise a Bluetooth module. The microprocessor is programmed by an external mobile equipment100via the Bluetooth module. The external mobile equipment100sends instructions to the microprocessor via the Bluetooth module, and the microprocessor controls the first multiplexer switch to select one of the plurality of input signal interface circuits to work according to the instructions. The microprocessor can comprise a serial communication circuit; an external equipment200sends instructions to the microprocessor via the serial communication circuit, and the microprocessor controls the first multiplexer switch to select one of the plurality of input signal interface circuits to work according to the instructions. The signal converter further comprises a rotary switch or button; instructions are sent to the microprocessor via the rotary switch or button, and the microprocessor controls the first multiplexer switch to select one of the plurality of input signal interface circuits to work according to the instructions. The signal converter comprises a housing1and a circuit board disposed in the housing1. All the circuits are disposed on the circuit board. The housing1is provided with an input signal status indicator21, a power status indicator22, and an output signal status indicator23. Specifically, for example, if the indicator light is always on, it means the selection is correct, and if the indicator light constantly flashes, it means the selection is wrong, and the user needs to check whether the wiring is correct. Specifically, the programming software of an external mobile equipment100, such as a smartphone, can select the signal input type, power input type and signal output type, when the smartphone transmits an instruction to the Bluetooth module, the Bluetooth module receives and transfers the instruction to the microprocessor MCU, the microprocessor MCU controls a corresponding multiplexer switch to select a corresponding signal input type, power input type and signal output type, and when the status indicator light is normally on, the signal conversion can be started. Or perhaps, the external equipment200is a PC, the programming software of the PC can select the signal input type, power input type and signal output type, when the PC transmits an instruction to the serial communication circuit, the serial communication circuit receives and transfers the instruction to the microprocessor MCU, the microprocessor MCU controls a corresponding multiplexer switch to select a corresponding signal input type, power input type and signal output type, and when the status indicator light is normally on, the signal conversion can be started.

Preferably, the housing1comprises a plurality of rotary switches24; the rotary switches24can select a signal input type, power input type and signal output type. Specifically, when the user rotates the rotary switches24, the rotary switches24transmit an instruction to the microprocessor MCU, the microprocessor MCU controls a corresponding multiplexer switch to select a signal input type, power input type and signal output type, and when the status indicator light is normally on, the signal conversion can be started. Or perhaps, the housing1can be provided with a plurality of buttons, the function of the buttons is consistent with that of the rotary switches, that is, to select a signal input type, power input type and signal output type, which will not be repeated herein.

The input signals comprise 0-10 VDC signals, pulse-width modulation (PWM) signals, 4-20 mA signals, serial communication signals, line voltage switching signals and 24 V temperature control switching signals. Preferably, the plurality of input signal interface circuits comprises a divider, filter and protection module for inputting 0-10 VDC signals, a PWM signal processing module for inputting PWM signals, a 4-20 mA signal processing module for inputting 4-20 mA signals, a four-line serial port to single line serial port and single line serial port signal processing module for inputting serial communication signals, a line voltage switching signal processing module for inputting line voltage switching signals, and a temperature control switching signal processing module for inputting 24 V temperature control switching signals. The serial communication signals are corresponding to communication protocols, and the signal converter supports multiple serial communication signal inputs with different communication protocols. The signal converter supports multiple communication protocols 1, 2, 3, and so on, such as ClimateTalk, customized Modbus, of the input end. The protocol can be selected through the mobile App or PC software or panel button.

The power circuit comprises a plurality of power input interface circuits and a second multiplexer switch; the plurality of power input interface circuits is disposed side by side; input terminals of the plurality of power input interface circuits are connected to corresponding input powers, and output terminals of the plurality of power input interface circuits are connected to the second multiplexer switch; in operation, the microprocessor controls the second multiplexer switch to select one of the plurality of power input interface circuits to work. The input powers comprise +5 VDC USB power supply, between +12 VDC and +24 VDC input power, and dry battery DC power supply. The output voltage of each power input interface circuit is standard, such as +3.3 VDC, +12 VDC, and so on, so as to provide standard power supply for each circuit. Each power input interface circuit is just a simple DC-DC conversion. There are detailed examples in the textbooks, which are not described herein.

A plurality of output signal interface circuits is disposed side by side; the plurality of output signal interface circuits is connected to a third multiplexer switch; the microprocessor controls the third multiplexer switch to select one of the plurality of output signal interface circuits to output a corresponding output signal via an output terminal of the plurality of output signal interface circuits. The output signal comprises a 0-10 VDC signal, pulse-width modulation (PWM) signal, 4-20 mA signal, serial communication signal, line voltage switching signal and 24 V temperature control switching signal. The power circuit can supply +24 VDC or +12 VDC power to a system controller or potentiometer of a user side. Preferably, the plurality of output signal interface circuits comprises a 0-10 VDC voltage processing module for outputting 0-10 VDC signals, a PWM signal processing module for outputting PWM signals, a 4-20 mA signal processing module for outputting 4-20 mA signals, a temperature control switching signal processing module for outputting 24 V temperature control switching signals, a line voltage switching signal processing module for outputting line voltage switching signals, and an output power processing circuit for outputting 24 V or 12 VDC power supply. The aforesaid output signal interface circuits are all related art and are not repeated herein.

FIG. 10illustrates a specific application of the signal converter as described in the disclosure. The programming software of a smartphone transmits an instruction to the Bluetooth module, the Bluetooth module receives and transfers the instruction to the microprocessor MCU, the microprocessor MCU controls the first multiplexer switch to select the divider, filter and protection module to input 0-10 VDC signals to an electrical equipment, the microprocessor MCU convert the 0-10 VDC signals into PWM signals and controls the third multiplexer switch to select the PWM signal processing module to work and output the PWM signals to the ECM.