CN203940910U - A kind of liquid low discharge standard set-up of dual Piston rack pinion - Google Patents

Abstract

The utility model discloses a kind of liquid low discharge standard set-up of dual Piston rack pinion.Dual Piston tooth bar-gear liquid cylinder pressure in the utility model is fixed by screws on base, base left and right sides is mounting knob all, servomotor coordinates rotation by key with the high class gear tooth bar of hydraulic cylinder, the left and right water delivering orifice of hydraulic cylinder is connected with buffer pocket by stainless joint respectively, and pressure transducer and temperature sensor are equipped with respectively in buffer pocket both sides; Buffer pocket front and back sides is connected with solenoid valve by ripple flexible pipe respectively; Wherein the water inlet of entering water electromagnetic valve is connected with water tank inlet, and the water delivering orifice that goes out water solenoid valve is connected with tested flowmeter by angle coupling.The utility model be take hydraulic cylinder volume as measurement standard, utilizes scrambler that piston displacement, speed are fed back to control system, realizes a closed-loop measuring system.

Description

A kind of liquid low discharge standard set-up of dual Piston rack pinion

Technical field

The utility model relates to a kind of low discharge standard set-up, especially relates to a kind of liquid low discharge standard set-up of dual Piston tooth bar-gear.

Background technology

In recent years, the research work of liquid Small flowrate measurement aspect is carried out in a lot of scientific research institutions, and liquid Small flowrate measurement is more and more common with the application that is controlled at the fields such as semiconductor manufacturing industry, bioengineering, medical science chemical industry.

At present, piston type flow standard device is widely used in liquid low discharge metering verification system, and it is high that it has accuracy, easily realizes the advantages such as robotization.But there is complex structure in traditional piston flow standard set-up, device one-piece construction distance, carrying is inconvenient, and each run carries out all can only examining and determine single flowmeter, the not high deficiency of efficiency.

Summary of the invention

For the deficiency of background technology, the purpose of this utility model is to provide a kind of liquid low discharge standard set-up of dual Piston tooth bar-gear.

The utility model solves the technical scheme that its technical matters adopts:

Dual Piston tooth bar-gear liquid cylinder pressure in the utility model is fixed by screws on base, base left and right sides is mounting knob all, servomotor coordinates rotation by key with the high class gear tooth bar of hydraulic cylinder, the left and right water delivering orifice of hydraulic cylinder is connected with buffer pocket by stainless joint respectively, and pressure transducer and temperature sensor are equipped with respectively in buffer pocket both sides; Buffer pocket front and back sides is connected with solenoid valve by ripple flexible pipe respectively; Wherein the water inlet of entering water electromagnetic valve is connected with water tank inlet, and the water delivering orifice that goes out water solenoid valve is connected with tested flowmeter by angle coupling.

The beneficial effects of the utility model:

1. the liquid low discharge standard set-up of a kind of dual Piston tooth bar-gear of the utility model is a set of fairly perfect active liquid flow standard device, its measurement range is 100～2000mL/min, can examine and determine flowmeter in haemodialysis purification plant prover and corresponding range ability etc., expanded uncertainty is 0.5% (k=2).

2. what device adopted is dual Piston gear-tooth bar hydraulic cylinder, drives the gear of hydraulic cylinder by servomotor, thus the operation simultaneously in the cavity of left and right of the piston of driven gear bar, calibrating when realizing two tested flowmeters.

3. whole device be take hydraulic cylinder volume as measurement standard, utilizes scrambler that piston displacement, speed are fed back to control system, realizes a closed-loop measuring system.Pressure transducer and temperature sensor have been installed simultaneously can carry out temperature pressure compensation to system, has greatly improved the measuring accuracy of device.

Accompanying drawing explanation

Fig. 1 is the schematic three dimensional views of the utility model device

In figure: 1, pressure transducer; 2, buffer pocket; 3, temperature sensor; 4, solenoid valve; 5, corrugated flexible hose; 6, water tank inlet; 7, solenoid valve; 8, water tank base for supporting; 9, angle coupling; 10, front straight tube; 11, tested flowmeter; 12, rear straight tube; 13, front straight tube; 14, tested flowmeter; 15, rear straight tube; 16, reserve tank; 17, solenoid valve; 18, solenoid valve; 19, temperature sensor; 20, buffer pocket; 21, stainless joint; 22, pressure transducer; 23, handle; 24, angle coupling; 25, servomotor; 26, encoder for servo motor; 27, dual Piston gear-tooth bar hydraulic cylinder; 28, stainless joint; 29, base.

Embodiment

As shown in Figure 1, dual Piston tooth bar-gear liquid cylinder pressure 27 is fixed by screws on base 29, base 29 left and right sides are mounting knob 23 all, servomotor 25 coordinates rotation by key with the high class gear tooth bar of hydraulic cylinder 27, the left and right water delivering orifice of hydraulic cylinder 27 all passes through stainless joint 28,21 and is connected with buffer pocket 2,20, and pressure transducer 1,22 and temperature sensor 3,19 are equipped with respectively in buffer pocket 2,20 both sides; Buffer pocket 2,20 front and back sides are connected with solenoid valve 7,4,17,18 by ripple flexible pipe 5 respectively; Wherein the water inlet of solenoid valve 4,17 is connected with water tank inlet 6, and water tank inlet 6 is placed on water tank base for supporting 8, and the water delivering orifice of solenoid valve 7,18 is connected with tested flowmeter 11,14 by angle coupling 9,24.Before flowing through, straight tube 10,13 flows into tested flowmeter 11,14, and after flowing through afterwards, straight tube 12,15 enters reserve tank 16.

Hydraulic cylinder 27 is standard dual Piston tooth bar-gear liquid cylinder pressure, and what it adopted is high-precision gear and tooth bar, and key position is all to adopt aluminium alloy and stainless steel to make, and has anticorrosive property, and reduced cost when guaranteeing precision.The water delivering orifice of hydraulic cylinder 27, can be realized smooth Exhaust Gas, the stability while being conducive to improve device operation upward when device horizontal positioned.The left and right water delivering orifice of hydraulic cylinder 27 connects by stainless joint 28,22.Buffer pocket 2,20 is equipped with respectively pressure transducer 1,22 and temperature sensor 3,19, and deformation error temperature and pressure being caused according to the thermal expansivity of hydraulic cylinder and elasticity coefficient is revised, and by this method device is done to temperature and pressure compensation.Buffer pocket 2,20 front and back sides are connected with solenoid valve 4,7,17,18 respectively, and the water inlet of solenoid valve 4,17 is connected with water tank inlet 6, and the water delivering orifice of solenoid valve 7,18 is connected with tested flowmeter 11,14.Encoder for servo motor 26 is arranged on the top of servomotor 25, by the position feedback of piston rod to control system; Control system is comprised of slave computer MSP430 single-chip microcomputer and host computer PC, and its function is speed, the position of control piston motion, gathers tested flow meter signal, and sensor signal is analyzed verification result.

The course of work of the present utility model is as follows: when slave computer control servomotor 25 drives the piston of the left and right gear bar of hydraulic cylinder 27 to produce fluid source with stabilized speed operation simultaneously, open solenoid valve 7,18, shut electromagnetic valve 4,17, through buffer pocket 2, the 20 tested flowmeter 11,14 of flowing through simultaneously, thereby reached the effect of simultaneously examining and determine two tested flowmeters 11,14.Using hydraulic cylinder 27 as metering volume standard, encoder for servo motor 26 by the speed of piston movement and Displacement Feedback to control system.Speed, position and the time of the motion of control system control piston, by calculating the volumetric flow rate of the liquid of exudate cylinder pressure 27 in certain Measuring Time, examine and determine tested flowmeter 11,14.

$q_s=\frac{V_s}{t}=\frac{{\mathrm{\πD}}^{2}L}{4t}$

$E=\frac{|q-q_s|}{q_s}\×100\%$

In formula, each parameter is respectively:

Q _s---normal flow, mL/min

V _s---hydraulic cylinder is got rid of liquid volume, mL

T---Measuring Time, s

D---cylinder diameter, cm

L---piston displacement, cm

The deviation of E---tested flowmeter.

Claims (1)

1. the liquid low discharge standard set-up of a dual Piston rack pinion, it is characterized in that: dual Piston tooth bar-gear liquid cylinder pressure (27) is fixed by screws on base (29), base (29) left and right sides is mounting knob (23) all, servomotor (25) coordinates rotation by key with the high class gear tooth bar of hydraulic cylinder (27), a left side for hydraulic cylinder (27), right water delivering orifice is respectively by stainless joint (28, 21) with buffer pocket (2, 20) be connected, buffer pocket (2, 20) pressure transducer (1 is equipped with respectively in both sides, 22) and temperature sensor (3, 19), buffer pocket (2,20) front and back sides is connected with solenoid valve (7,4,17,18) by ripple flexible pipe (5) respectively, wherein the water inlet of solenoid valve (4,17) is connected with water tank inlet (6), and the water delivering orifice of solenoid valve (7,18) is connected with tested flowmeter (11,14) by angle coupling (9,24) respectively.