Metering pump with constant speed and constant pressure

Abstract

The invention provides a metering pump with constant speed and constant pressure, comprising a power unit, conveyer devices and a microcomputer. Two sets of conveyer devices are provided in the invention. Each conveyer device is equipped with a worm-wheel case, a rolling-typed screw rod, a connecting bar and two pump cylinders; wherein, the worm-wheel case is internally connected with a worm wheel, a worm and an outside nut of the rolling-typed screw rod, a pull rod is connected with the worm-wheel case and a support plate, the worm is engaged with the worm wheel which is connected with the outside nut of the rolling-typed screw rod, the rolling-typed screw rod and the connecting bar are connected into a connector, a centralizing bracket is arranged at the joint of the rolling-typed screw rod and the connecting bar, one end of the rolling-typed screw rod and one end of the connecting bar are connected with pistons, each piston corresponds to one pump cylinder, the top end of the pump cylinder is equipped with a choke plug and a coif, and the choke plug is connected with a three-way piece which is provided with an outlet valve, an inlet valve and a pressure sensor. The metering pump of the invention can continuously provide pulse-free fluid with constant speed and constant pressure; the adjustment range of the discharge capacity reaches five-digit number; and the measurement accuracy exceeds 1%.

Description

technical field [0001] The invention relates to a mechanical device for metering conveyed medium, in particular to a metering pump, which belongs to the field of chemical machinery. Background technique [0002] Metering pump is a kind of precision equipment mainly used to measure the conveyed medium. The structure of metering pump is usually single cylinder or double cylinder. [0003] There are usually two types of metering pumps: plunger type and piston type. The usual metering method is the cross-sectional area of ​​the plunger or piston multiplied by the length of the plunger or piston moving in the pump cylinder. The double-cylinder metering pump is usually piston type. [0004] The current metering pump mainly has the following shortcomings: [0005] 1. When the medium is conveyed, pulses will be generated, and the medium cannot be conveyed continuously, at a constant speed and at a constant pressure; [0006] 2. The pump and conveying medium cannot be at the same t...

AI Technical Summary

Problems solved by technology

[0005] 1. When the medium is conveyed, pulses will be generated, and the medium cannot be conveyed continuously, at a constant speed and at a constant pressure;

[0006] 2. The pump and conveying medium cannot be at the same time, and must wait until the medium is conveyed;

[0007] 3. The pump inlet time plus pre-compression preparation time of the double-cylinder pump should be less than the medium discharge time, which limits the discharge speed of the pump;

[0008] 4. The displacement adjustment range is not wide enough;

[0009] 5. The instability of the pump cylinder size makes the pump metering accuracy not enough

[0010] Due to these shortcomings, it is difficult for existing metering pumps to meet the metering requirements in various states

Images