A power type nozzle reference voltage controllable circuit for inkjet printer

Abstract

The utility model discloses a power-type nozzle reference voltage controllable circuit for an inkjet printer, comprising a CPU, a triode switch, an LMR16030 and a nozzle reference voltage. The utility model uses the CPU for intelligent control and cooperates with the triode switch to achieve rapid response; uses the LMR16030 low-voltage difference linear regulator for precise voltage stabilization; dynamically adjusts the voltage through PWM control and a closed-loop feedback mechanism to adapt to different loads, solves the complexity and instability of traditional circuits in power-on and power-off timing and voltage control, enables the circuit to accurately control the nozzle reference voltage, and maintains voltage stability even when the load changes, thereby significantly improving the printing quality and reliability of the device.

Description

Technical Field

[0001] The utility model relates to the field of printers, in particular to a power-type nozzle reference voltage controllable circuit for an inkjet printer. Background Art

[0002] There is a major pain point in the waveform output control of the printer. First, the reference voltage control of most printhead circuits requires power output and power-on and power-off timing requirements. Voltage control has advantages in terms of ease of use, performance, and reliability in engineering implementation, but there is also a problem that cannot be ignored, that is, a large number of switch signals and trigger signals are required in the power-on and power-off timing requirements, which leads to the complexity of circuit design. This complexity needs to be considered to ensure the reliability of the application. Summary of the invention

[0003] In order to solve the above-mentioned technical problems, the utility model provides a power type nozzle reference voltage controllable circuit for an inkjet printer.

[0004] The technical solution of the utility model is achieved in this way:

[0005] The utility model discloses a power type nozzle reference voltage controllable circuit for an inkjet printer, comprising a CPU, a triode switch, an LMR16030 and a nozzle reference voltage.

[0006] The CPU is responsible for receiving and processing control signals, adjusting the working mode of the circuit according to the working status and requirements of the printer, sending instructions to the transistor switch, and controlling the output of the nozzle reference voltage;

[0007] The transistor switch is used to control the on and off of the current. When the CPU sends an instruction, the transistor switch responds quickly to control the output of the nozzle reference voltage.

[0008] The LMR16030 charges and discharges the capacitor through PWM control to perform dynamic voltage stabilization;

[0009] The nozzle reference voltage is used to control the ink jetting force and printing quality during the inkjet printing process.

[0010] The first pin of the LMR16030 is connected to one end of the first inductor L1 through the first capacitor C25, the first capacitor C25 is also connected to the eighth pin of the LMR16030, the eighth pin of the LMR16030 is also connected to the seventh pin of the LMR16030 through the first diode D36, the other end of the first inductor L1 is connected to the fifth pin of the LMR16030 through the first resistor R27, the fifth pin of the LMR16030 is also connected to one end of the second resistor R25, and the other end of the second resistor R25 is respectively connected to the first diode D36 and one end of the second capacitor C143.

[0011] One end of the first inductor L1 is also connected to the other end of the second capacitor C143, the other end of the second capacitor C143 is connected to one end of the third capacitor C33, the other end of the third capacitor C33 is connected to one end of the second capacitor C143, one end of the third capacitor C33 is also connected to one end of the fourth capacitor C31, the other end of the fourth capacitor C31 is connected to the other end of the third capacitor C33, one end of the fourth capacitor C31 is also connected to one end of the fifth capacitor C21, the other end of the fifth capacitor C21 is connected to the other end of the fourth capacitor C31, one end of the fifth capacitor C21 is also connected to one end of the sixth capacitor C22, the other end of the sixth capacitor C22 is connected to the other end of the fifth capacitor C21.

[0012] One end of the sixth capacitor C22 is connected to the third resistor R12 through the second inductor L26, and the third resistor R12 is connected to the other end of the sixth capacitor C22 through the LED lamp. The second inductor L26 is also connected to one end of the seventh capacitor C174, and the other end of the seventh capacitor C174 is connected to the LED lamp. One end of the seventh capacitor C174 is also connected to one end of the eighth capacitor C175 and the first pin of the plug-in JP, respectively. The other end of the eighth capacitor C175 is respectively connected to the other end of the seventh capacitor C174 and the second pin of the plug-in JP, and one end of the seventh capacitor C174 is connected to AGND.

[0013] The second pin of the LMR16030 is connected to the third pin of the LMR16030 through the fourth resistor R18, the third pin of the LMR16030 is also connected to one end of the fifth resistor R24, the other end of the fifth resistor R24 ​​is connected to the sixth pin of the LMR16030 through the ninth capacitor C29, the fourth pin of the LMR16030 is connected to the ninth capacitor C29 through the sixth resistor R26, and the ninth capacitor C29 is also connected to the seventh pin of the LMR16030 through the ground.

[0014] One end of the fifth resistor R24 ​​is also connected to the other end of the fifth resistor R24 ​​through the tenth capacitor C14, one end of the tenth capacitor C14 is connected to the collector of the transistor, the other end of the tenth capacitor C14 is connected to the emitter of the transistor, the base of the transistor is respectively connected to one end of the seventh resistor R8 and the ninth resistor R29, the other end of the seventh resistor R8 is connected to SWITCH_VBS, the other end of the ninth resistor R29 is connected to the fourth resistor R18 through the eleventh capacitor C25, one end of the eleventh capacitor C25 is also connected to the ferrite bead BL2, and the ferrite bead BL2 is connected to VPP through the second diode D23.

[0015] The VPP is a power supply, and the power input range is 24V-42V; SWITCH_VBS is an IO drive signal; the DC-DC power supply IC of LMR16030; the transistor is a PNP transistor; AGND is the nozzle reference voltage; the ferrite bead BL2 and the eleventh capacitor C25 form a filter circuit to filter the VPP power input; the second resistor R25 and the first resistor R27 form a voltage divider circuit to input the fifth pin of LMR16030 to set the starting voltage, and the second capacitor C143 plays a role in stabilizing the voltage to prevent the circuit from being disturbed and causing false triggering protection, thereby enhancing the circuit reliability; the ninth capacitor C29 is a bootstrap capacitor, and the eleventh capacitor C25 is a soft start capacitor; the sixth resistor R26 sets the output PWM frequency; the first diode D36 is a Schottky diode, which helps the inductor L1 to continue current; the second resistors R25 and R27 form a negative feedback network to compare the PIN5 input after the output level is divided with the reference level.

[0016] Beneficial effects:

[0017] The CPU is used for intelligent control, and the transistor switch is used to achieve fast response. The LMR16030 low-dropout linear regulator is used for precise voltage regulation. The voltage is dynamically adjusted through PWM control and closed-loop feedback mechanism to adapt to different loads, solving the complexity and instability of traditional circuits in power-on and power-off timing and voltage control. The circuit can accurately control the reference voltage of the printhead and maintain voltage stability even when the load changes, significantly improving the printing quality and equipment reliability.

[0018] The filter circuit of ferrite beads and capacitors, bootstrap capacitors and soft-start capacitors to reduce startup shock, and LED lights and monitoring circuits to provide intuitive working status indications, enhance the circuit's anti-interference ability and stability, and provide a user-friendly monitoring method, so that the operator can understand the circuit status in real time, perform maintenance and adjustments in time, extend the service life of the equipment and reduce maintenance costs, and solve the problems of power supply noise, electromagnetic interference and current shock when the circuit starts, all of which may affect the stability and life of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the circuit framework of the utility model;

[0020] Figure 2 It is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0021] like Figure 1-Figure 2 As shown, the utility model is a power type nozzle reference voltage controllable circuit for an inkjet printer, comprising a CPU, a triode switch, an LMR16030 and a nozzle reference voltage.

[0022] The CPU is responsible for receiving and processing control signals, adjusting the working mode of the circuit according to the working status and requirements of the printer, sending instructions to the transistor switch, and controlling the output of the nozzle reference voltage;

[0023] The transistor switch is used to control the on and off of the current. When the CPU sends an instruction, the transistor switch responds quickly, thereby controlling the output of the nozzle reference voltage;

[0024] The LMR16030 charges and discharges the capacitor through PWM control to achieve dynamic voltage stabilization. It is a low voltage drop linear regulator that can provide a stable voltage output. In the circuit design of an inkjet printer, the LMR16030 can provide a stable reference voltage for the print head to ensure the consistency of printing quality.

[0025] The nozzle reference voltage is used to control the ink jetting force and printing quality during the inkjet printing process.

[0026] The first pin of the LMR16030 is connected to one end of the first inductor L1 through the first capacitor C25, the first capacitor C25 is also connected to the eighth pin of the LMR16030, the eighth pin of the LMR16030 is also connected to the seventh pin of the LMR16030 through the first diode D36, the other end of the first inductor L1 is connected to the fifth pin of the LMR16030 through the first resistor R27, the fifth pin of the LMR16030 is also connected to one end of the second resistor R25, and the other end of the second resistor R25 is respectively connected to the first diode D36 and one end of the second capacitor C143.

[0027] One end of the first inductor L1 is also connected to the other end of the second capacitor C143, the other end of the second capacitor C143 is connected to one end of the third capacitor C33, the other end of the third capacitor C33 is connected to one end of the second capacitor C143, one end of the third capacitor C33 is also connected to one end of the fourth capacitor C31, the other end of the fourth capacitor C31 is connected to the other end of the third capacitor C33, one end of the fourth capacitor C31 is also connected to one end of the fifth capacitor C21, the other end of the fifth capacitor C21 is connected to the other end of the fourth capacitor C31, one end of the fifth capacitor C21 is also connected to one end of the sixth capacitor C22, the other end of the sixth capacitor C22 is connected to the other end of the fifth capacitor C21.

[0028] One end of the sixth capacitor C22 is connected to the third resistor R12 through the second inductor L26, and the third resistor R12 is connected to the other end of the sixth capacitor C22 through the LED lamp. The second inductor L26 is also connected to one end of the seventh capacitor C174, and the other end of the seventh capacitor C174 is connected to the LED lamp. One end of the seventh capacitor C174 is also connected to one end of the eighth capacitor C175 and the first pin of the plug-in JP, respectively. The other end of the eighth capacitor C175 is respectively connected to the other end of the seventh capacitor C174 and the second pin of the plug-in JP, and one end of the seventh capacitor C174 is connected to AGND.

[0029] The second pin of the LMR16030 is connected to the third pin of the LMR16030 through the fourth resistor R18, the third pin of the LMR16030 is also connected to one end of the fifth resistor R24, the other end of the fifth resistor R24 ​​is connected to the sixth pin of the LMR16030 through the ninth capacitor C29, the fourth pin of the LMR16030 is connected to the ninth capacitor C29 through the sixth resistor R26, and the ninth capacitor C29 is also connected to the seventh pin of the LMR16030 through the ground.

[0030] One end of the fifth resistor R24 ​​is also connected to the other end of the fifth resistor R24 ​​through the tenth capacitor C14, one end of the tenth capacitor C14 is connected to the collector of the transistor, the other end of the tenth capacitor C14 is connected to the emitter of the transistor, the base of the transistor is respectively connected to one end of the seventh resistor R8 and the ninth resistor R29, the other end of the seventh resistor R8 is connected to SWITCH_VBS, the other end of the ninth resistor R29 is connected to the fourth resistor R18 through the eleventh capacitor C25, one end of the eleventh capacitor C25 is also connected to the ferrite bead BL2, and the ferrite bead BL2 is connected to VPP through the second diode D23.

[0031] The VPP is a power supply, and the power input range is 24V-42V; SWITCH_VBS is an IO drive signal; the DC-DC power supply IC of LMR16030; the transistor is a PNP transistor; AGND is the nozzle reference voltage; the ferrite bead BL2 and the eleventh capacitor C25 form a filter circuit to filter the VPP power input; the second resistor R25 and the first resistor R27 form a voltage divider circuit to input the fifth pin of LMR16030 to set the starting voltage, and the second capacitor C143 plays a role in stabilizing the voltage to prevent the circuit from being disturbed and causing false triggering protection, thereby enhancing the circuit reliability; the ninth capacitor C29 is a bootstrap capacitor, and the eleventh capacitor C25 is a soft start capacitor; the sixth resistor R26 sets the output PWM frequency; the first diode D36 is a Schottky diode, which helps the inductor L1 to continue current; the second resistors R25 and R27 form a negative feedback network to compare the PIN5 input after the output level is divided with the reference level.

[0032] Working process:

[0033] The high voltage VPP is initially filtered out of noise and stabilized by the filter circuit composed of the ferrite bead BL2 and the eleventh capacitor C25 to ensure the cleanliness and stability of the power input. Subsequently, the filtered voltage is input to the second pin of the LMR16030, and the third pin is used as the input voltage detection point. Once the input voltage is detected to be within the set range, the LMR16030 starts the internal MOS tube and performs PWM charging of a series of capacitors (including the second capacitor C143, the fifth capacitor C21, the sixth capacitor C22, the fourth capacitor C31 and the third capacitor C33) at a specific frequency through the inductor L1;

[0034] During the PWM charging process, the capacitor is gradually charged to a voltage close to the set 5V. When the capacitor voltage reaches the preset threshold and is compared with the reference level inside the LMR16030 through the negative feedback network (composed of the second resistor R25 and the first resistor R27), if the feedback signal is detected to be higher than the reference level, the internal MOS tube will be turned off. At this time, the first diode D36 is turned on to provide a freewheeling path for the inductor L1 to prevent voltage mutation and electromagnetic interference.

[0035] As the load consumes the energy stored in the capacitor, when the seventh pin of LMR16030 detects that the feedback signal is lower than the reference level through the negative feedback network, the internal MOS tube will restart and continue to charge the capacitor to form a closed-loop control to ensure the stability of the output voltage. This dynamic adjustment process is repeated to adapt to different printing requirements and load changes.

[0036] At the same time, the CPU monitors the working status of the entire circuit. According to the specific needs of the printer, it adjusts the output of the nozzle reference voltage by controlling the transistor switch. When the SWITCH_VBS signal is controlled to a low level, the transistor is turned on, allowing the reference voltage to be output to the nozzle; on the contrary, when the SWITCH_VBS signal is high, the transistor is turned off, closing the output of the nozzle reference voltage.

[0037] In addition, the circuit also includes a variety of protection components, such as bootstrap capacitor C29, soft-start capacitor C25, etc., which work together in the startup and stable working stages of the circuit to reduce the current impact at startup and improve the reliability of the circuit. The LED light and related monitoring circuits provide intuitive working status indication, which is convenient for the operator to conduct real-time monitoring and troubleshooting.

[0038] Working principle: The high voltage VPP is filtered and input to the second pin of LMR16030. The third pin detects that the input level meets the range, and starts the internal MOS to charge the second capacitor C143, the fifth capacitor C21, the sixth capacitor C22, the fourth capacitor C31 and the third capacitor C33 through the inductor L1 with a specific frequency PWM. When the capacitor is charged to the set 5V voltage, when it is detected that the feedback signal is higher than the reference level, the internal MOS is turned off, and the first diode D36 is turned on to freewheel the inductor L1. The output voltage is set:

[0039] Uout = ref * (R25 + R27) / R25;

[0040] When the load consumes the capacitor power, the seventh pin of LMR16030 detects that the feedback signal is lower than the reference level and then starts charging the internal MOS, and the cycle continues to achieve the effect of dynamic voltage regulation.

[0041] When the nozzle reference voltage needs to be started, the SWITCH_VBS signal is controlled to a low level to output the desired nozzle reference voltage. Conversely, when the nozzle reference voltage needs to be turned off, the SWITCH_VBS signal is controlled to a high level.

Claims

1. A power type nozzle reference voltage controllable circuit for an inkjet printer, characterized in that: Including CPU, transistor switch, LMR16030 and nozzle reference voltage, The CPU is responsible for receiving and processing control signals, adjusting the working mode of the circuit according to the working status and requirements of the printer, sending instructions to the transistor switch, and controlling the output of the nozzle reference voltage; The transistor switch is used to control the on and off of the current. When the CPU sends an instruction, the transistor switch responds quickly to control the output of the nozzle reference voltage; The LMR16030 charges and discharges the capacitor through PWM control to perform dynamic voltage stabilization; The nozzle reference voltage is used to control the ink jetting force and printing quality during the inkjet printing process.

2. The power type nozzle reference voltage controllable circuit for an inkjet printer according to claim 1, characterized in that: The first pin of the LMR16030 is connected to one end of the first inductor L1 through the first capacitor C25, the first capacitor C25 is also connected to the eighth pin of the LMR16030, the eighth pin of the LMR16030 is also connected to the seventh pin of the LMR16030 through the first diode D36, the other end of the first inductor L1 is connected to the fifth pin of the LMR16030 through the first resistor R27, the fifth pin of the LMR16030 is also connected to one end of the second resistor R25, and the other end of the second resistor R25 is respectively connected to the first diode D36 and one end of the second capacitor C143.

3. The power type nozzle reference voltage controllable circuit for an inkjet printer according to claim 2, characterized in that: One end of the first inductor L1 is also connected to the other end of the second capacitor C143, the other end of the second capacitor C143 is connected to one end of the third capacitor C33, the other end of the third capacitor C33 is connected to one end of the second capacitor C143, one end of the third capacitor C33 is also connected to one end of the fourth capacitor C31, the other end of the fourth capacitor C31 is connected to the other end of the third capacitor C33, one end of the fourth capacitor C31 is also connected to one end of the fifth capacitor C21, the other end of the fifth capacitor C21 is connected to the other end of the fourth capacitor C31, one end of the fifth capacitor C21 is also connected to one end of the sixth capacitor C22, the other end of the sixth capacitor C22 is connected to the other end of the fifth capacitor C21.

4. The power type nozzle reference voltage controllable circuit for an inkjet printer according to claim 3, characterized in that: One end of the sixth capacitor C22 is connected to the third resistor R12 through the second inductor L26, and the third resistor R12 is connected to the other end of the sixth capacitor C22 through the LED lamp. The second inductor L26 is also connected to one end of the seventh capacitor C174, and the other end of the seventh capacitor C174 is connected to the LED lamp. One end of the seventh capacitor C174 is also connected to one end of the eighth capacitor C175 and the first pin of the plug-in JP, respectively. The other end of the eighth capacitor C175 is respectively connected to the other end of the seventh capacitor C174 and the second pin of the plug-in JP, and one end of the seventh capacitor C174 is connected to AGND.

5. The power type nozzle reference voltage controllable circuit for an inkjet printer according to claim 2, characterized in that: The second pin of the LMR16030 is connected to the third pin of the LMR16030 through the fourth resistor R18, the third pin of the LMR16030 is also connected to one end of the fifth resistor R24, the other end of the fifth resistor R24 ​​is connected to the sixth pin of the LMR16030 through the ninth capacitor C29, the fourth pin of the LMR16030 is connected to the ninth capacitor C29 through the sixth resistor R26, and the ninth capacitor C29 is also connected to the seventh pin of the LMR16030 through the ground.

6. The power type nozzle reference voltage controllable circuit for an inkjet printer according to claim 5, characterized in that: One end of the fifth resistor R24 ​​is also connected to the other end of the fifth resistor R24 ​​through the tenth capacitor C14, one end of the tenth capacitor C14 is connected to the collector of the transistor, the other end of the tenth capacitor C14 is connected to the emitter of the transistor, the base of the transistor is respectively connected to one end of the seventh resistor R8 and the ninth resistor R29, the other end of the seventh resistor R8 is connected to SWITCH_VBS, the other end of the ninth resistor R29 is connected to the fourth resistor R18 through the eleventh capacitor C25, one end of the eleventh capacitor C25 is also connected to the ferrite bead BL2, and the ferrite bead BL2 is connected to VPP through the second diode D23.

7. The power type nozzle reference voltage controllable circuit for an inkjet printer according to claim 6, characterized in that: The VPP is a power supply, and the power input range is 24V-42V; SWITCH_VBS is an IO drive signal; the DC-DC power supply IC of LMR16030; the transistor is a PNP transistor; AGND is the nozzle reference voltage; the ferrite bead BL2 and the eleventh capacitor C25 form a filter circuit to filter the VPP power input; the second resistor R25 and the first resistor R27 form a voltage divider circuit to input the fifth pin of LMR16030 to set the starting voltage, and the second capacitor C143 plays a role in stabilizing the voltage to prevent the circuit from being disturbed and causing false triggering protection; the ninth capacitor C29 is a bootstrap capacitor, and the eleventh capacitor C25 is a soft start capacitor; the sixth resistor R26 sets the output PWM frequency; the first diode D36 is a Schottky diode; the second resistor R25 and R27 form a negative feedback network to compare the PIN5 input after the output level is divided with the benchmark reference level.

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