Pumps used in inkjet printers or inkjet printers-gear pumps

In many industrial inkjet printers (such as large-format UV, solvent, ink circulation systems), gear pumps are one of the most commonly used ink supply/circulation pumps.

In inkjet printing systems, the stability of liquid (ink) delivery directly affects printhead ejection quality, droplet consistency, and overall system reliability. While many consumer inkjet printers use piezoelectric pumps or Miniature Diaphragm Pumps, industrial inkjet printing equipment (such as UV, solvent, textile inkjet, and coding/marking industries) often uses gear pumps.

1. Main Uses of Gear Pumps in Inkjet Printers

Gear pumps are typically used for:

✔ Ink Circulation

Maintaining a stable flow of ink within the printhead, preventing sedimentation.

Especially for devices containing pigment ink.

✔ Ink Supply/Ink Delivery

Delivering ink from the main cartridge to the printhead at a stable flow rate and pressure.

✔ Negative Pressure Control System (Some Models)

While negative pressure is often controlled by a miniature air pump or negative pressure module, a gear pump can assist in maintaining stable pressure.

✔ Filtration Circulation

Long-term ink circulation and filtration through a filter cartridge.

2. Why Use a Gear Pump? Key Advantages

• Stable Flow Rate and Extremely Low Pulsation

Inkjet printing requires extremely stable pressure and flow rate, while gear pumps deliver virtually no pulsation, making them ideal for:

• Precision printheads (EPSON, Ricoh, Konica Minolta)
• UV/solvent-based inks with high viscosity

• Chemical Resistance and Adaptability to Various Inks

Gear pump options include:

• PEEK gears
• Stainless steel gears
• PPS/PTFE seals

Compatible with: UV, solvent, water-based, oil-based, and other inks.

• Capable of Continuous Operation for Long Term

Gear pumps have a simple structure and high mechanical reliability, making them suitable for 7×24 continuous printing.

• Can Be Miniaturized Very Highly

Miniature Gear Pumps are commonly used in desktop inkjet printers with limited space.

3. Disadvantages of Gear Pumps (Related to Inkjet Systems) 

⚠ High pressure, unsuitable for direct printhead negative pressure control

Printheads generally require negative pressure (-3～-5 kPa), while gear pumps are positive pressure pumps, therefore they often need to be used in conjunction with:

• Pressure reducing valve
• Dalton pressure chamber
• SoftBag ink bag system
• Miniature air pump providing negative pressure 

⚠ Sensitive to impurities

The gear clearance is extremely small, requiring:

• High-grade filter (5–10 µm)
• To prevent pigment deposits 

⚠ Ink temperature affects viscosity and flow rate

A temperature control system is required (especially for UV inks).

4. Comparison with Common Printer Pumps

5. Typical Specifications of Gear Pumps in the Inkjet Printing Industry (Reference)

• Flow Rate: 1–2 L/min
• Pressure: 2–1.0 MPa
• Material:PEEK / Stainless Steel / PPS
• Drive: Brushless DC Motor (BLDC) or Stepper Motor
• Noise: 40–60 dB (depending on ink and speed)
• Compatible Inks: UV, Solvent, Water-based, Oil-based

6. Common Brands Providing Gear Pumps for the Printing Industry 

(The following are common company types in the industry for reference)

Micropump (USA)

Idex / Oberdorfer

German micro-gear pump manufacturers

Some specialized Chinese micro pump manufacturers (such as Tide Smart Technology (Shanghai) Co.,Ltd.)