In the beginning, gear pumps were hydraulic. Now, because everyone pays more attention to the concept of energy saving and environmental protection, the mature use of servo motors and the sharp reduction in prices, in recent years, all-electric precision gear pumps have gradually increased and are subdivided into development trends. It has the following characteristics:

1. The electro-hydraulic "gear pump" is a new "gear pump" which integrates hydraulic and electric transmission. It combines the high performance of a full hydraulic "gear pump" with the advantages of environmental protection and energy saving. This electro-hydraulic compound "gear pump" has become the development trend of "gear pump" technology.

2. The fully hydraulic gear pump has many unique advantages in the form of precision molding and complex products. It has evolved from the traditional single-cylinder liquid-filled and multi-cylinder liquid-filled types to the existing double-plate once-through type. The double-plate direct pressure type is symbolic, but its control technology system is difficult, the processing efficiency is high, and the hydraulic technology is difficult to master.

3. The all-electric gear pump has a series of advantages, especially in terms of environmental protection and energy saving. It is reported that excellent industrial gear pumps at this stage can save up to 70% of energy. In addition, due to the high precision of the servo motor injection control, the speed is stable, and it can be adjusted in multiple stages. However, the service life of the all-electric gear pump is not as good as that of the all-hydraulic gear pump. In order to ensure the accuracy of the full hydraulic gear pump, a servo valve must be used for closed-loop control. Servo valves are expensive and add to the cost.

In the total cost of injection molding products, electricity accounts for a relative proportion. According to the requirements of "gear pump" and equipment processing technology, the power consumption ratio of "gear pump" oil pump motor and all machinery and equipment consumption reaches 50%-65%, so it has the potential of environmental protection and energy saving. All-electric injection molding machines have inherent advantages in the actual effect of environmental protection and energy saving. However, as mentioned above, the overall cost of such production is high, resulting in a very limited range of applications; at this stage, the industry is largely monopolized by Japanese companies.

The introduction of energy-saving and environmental protection into injection molding machines, and the development and design of environmentally-friendly and energy-saving injection molding machines are also the key trends in the development of international and domestic injection molding machine expertise and technology. This type of technology mainly includes frequency conversion environmental protection and energy saving, variable frequency pump environmental protection and energy saving, servo control environmental protection and energy saving. The actual effect of environmental protection and energy saving can also reach the range of 30% to 70%.

According to the characteristics of gear pumps and the development prospects of the industry, in order to better develop gear pumps, it is necessary to formulate specific measures to expand the market demand for gear pump training according to relevant industries and international market conditions.