CN204461970U - A kind of measurement mechanism controlling the standard instruments calibrating of air flow source - Google Patents

Abstract

A measuring device for standard appliance verification that can control the airflow source, including a linear suction system, a measurement and test system, and a control system for controlling the suction system and the measurement and test system, characterized in that: the measurement and test system includes The constant pressure flow measurement unit used to verify the standard instrument of cigarette standard rod and ventilation rate standard rod, and the constant current pressure measurement unit used to verify the standard instrument of cigarette paper air permeability, the two units are connected in parallel and installed on the linear pump The working interface at the air outlet at the front end of the piston cylinder in the suction system, and the test mode conversion between the two units is controlled by the mode conversion switch set in the control system. The outstanding advantage of the utility model is that it can realize the integration of the functions of constant current pressure measurement and constant pressure flow measurement, that is, it can realize the verification and measurement of air permeability standard instrument, cigarette draw resistance standard rod and ventilation rate on the same instrument device.

Description

A measuring device for standard appliance verification with controllable airflow source

Technical field:

The utility model belongs to the field of standard appliance verification of tobacco instruments, specifically, it is a measuring device for standard appliance verification that can control the airflow source, which can be used for standard appliance verification of cigarette standard rods and ventilation rate standard rods (constant pressure flow measurement) ), it can also be used to test the air permeability standard instrument of cigarette paper (constant current pressure measurement).

Background technique:

Usually, when verifying the air permeability standard appliance of cigarette paper, the positive pressure is provided by compressed air, and the throttling method is adopted, and the flow meter is used to monitor the air path. value to get the air permeability parameter. Cigarette paper air permeability flow discs are divided into positive pressure and negative pressure, with a flow range of 0.05L/min-60L/min. Under laboratory conditions, the negative pressure generator cannot provide the negative pressure flow required by the large flow disc. CN102507408A discloses a piston-type constant pressure controllable air flow source flow measuring device, which can measure the air permeability of cigarette paper as a standard instrument, and can realize experimental research under different set pressure difference conditions in the research field of tobacco laboratory special equipment Work.

CFO (Critical Flow Orifice) method is used to form a constant flow when verifying the standard appliance of cigarette draw resistance. The flow rate of the constant airflow formed by CFO is inherent in CFO and cannot be adjusted or changed, and the aperture of CFO is very small, and the airflow in the hole is close to the higher flow velocity of the speed of sound, which will generate a certain amount of heat, cause energy loss, and cannot pass through the detection hole Compensating the temperature of the internal airflow also causes problems such as the attenuation of the flow rate with the increase of the resistance on the airflow path, resulting in a large deviation between the actual gas flow rate and the CFO theoretical flow rate. CN102419297A discloses a piston-type constant-flow controllable airflow source pressure measuring device, which can measure the draw resistance of cigarette draw resistance standard rods and ventilation rate standard rods, and can realize pressure measurement research work under different flow rates.

When testing cigarette paper air permeability standard instruments or cigarette draw resistance standard rods and ventilation rate standard rods, it is completed by two instruments: the cigarette paper air permeability standard instrument test device, cigarette draw resistance standard rods and ventilation rate standard rod test devices. Therefore, the verification and measurement of air permeability standard appliance, cigarette draw resistance standard rod and ventilation rate cannot be realized on the same instrument.

Invention content:

The purpose of this utility model is to realize the verification device integrating constant current pressure measurement and constant pressure flow measurement into one, which is specially developed for the above-mentioned state of the prior art. The device can not only measure the draw resistance of standard rods of cigarette draw resistance and ventilation rate standard rods, but also realize the pressure measurement and research work under different flow rates; The research field of laboratory special equipment can realize experimental research work under different set pressure difference conditions.

The purpose of this utility model is achieved through the following technical solutions:

A measuring device for standard appliance verification that can control the airflow source, including a linear suction system, a measurement and test system, and a control system for controlling the suction system and the measurement and test system, wherein: the measurement and test system includes a device for testing cigarettes The constant pressure flow measurement unit for the verification of the standard rod and the ventilation rate standard rod standard appliance, and the constant current pressure measurement unit for the verification of the cigarette paper air permeability standard appliance, the two units are connected in parallel and installed in the linear suction system On the working interface at the air outlet at the front end of the middle piston cylinder, and the test mode conversion between the two units is controlled by the mode conversion switch set in the control system;

The linear suction system is composed of a suction piston, a screw connected to the piston rod, and a servo motor that drives the screw to rotate, and the rotation of the servo motor and the limit switch in the movement range of the piston rod are controlled by the control system;

The constant pressure flow measurement unit includes a working interface, a working solenoid valve, a working solenoid valve for front and rear end measurement, a front and rear end isolation solenoid valve, a flow meter, a fixture for constant pressure flow measurement standard equipment, a front interface of the fixture, and a The differential pressure sensor at the intake end, the temperature sensor located in the fixture, all the solenoid valves, differential pressure sensors and temperature sensors in the unit are electrically connected to the control system; the flowmeter can be a mass flowmeter or a volume flow meter.

The constant current pressure measurement unit includes a working interface, a working solenoid valve, a constant current pressure measurement standard fixture fixture, a front interface of the fixture, a pressure sensor arranged at the inlet end of the fixture, and a temperature sensor arranged in the fixture, The working solenoid valve, pressure sensor and temperature sensor in the unit are all electrically connected with the control system;

An air path leading to the atmosphere is also provided on the working interface, and a return solenoid valve and a noise reduction filter are installed on the air path.

In the utility model, the lead screw and the servo motor in the linear suction system are connected through a coupling, and front and rear end limit switches are installed at the front and rear ends of the lead screw.

The linear suction system can be one group or multiple groups connected in parallel; the suction piston can be connected in one group or multiple groups in parallel.

The different movement directions of the piston can form two states of positive pressure and negative pressure during measurement.

The control system is composed of a servo motor motion control system, an operation and display system, a signal processing control system, and a measurement control system.

The outstanding advantage of the utility model is that it can realize the integration of the functions of constant current pressure measurement and constant pressure flow measurement, that is, it can realize the verification and measurement of air permeability standard instrument, cigarette draw resistance standard rod and ventilation rate on the same instrument device. The device of the utility model can not only measure the draw resistance of the cigarette draw resistance standard rod and the ventilation rate standard rod, but also realize the pressure measurement and research work under different flow rates; at the same time, it also has the measurement function of the cigarette paper air permeability standard instrument, Realize experimental research work under different set pressure difference conditions.

Description of drawings

Fig. 1 is a schematic diagram of the structure and connection relationship of the present utility model.

Labels in the figure: 1. Control system, 2. Front limit switch, 3. Rear limit switch, 4. Rear screw seat, 5. Lead screw, 6. Screw nut, 7. Connection block, 8. Piston seat, 9. Front screw seat, 10. Coupling, 11. Servo motor, 12. Piston cylinder, 13. Piston rod, 14. Piston, 15. Working interface, 16. Working solenoid valve, 17. Return solenoid valve, 18. Noise elimination filter, 19-1, front interface of constant current pressure measurement fixture, 19-2, front interface of constant pressure flow measurement fixture, 20-1, constant current pressure measurement standard instrument fixture, 20-2, Fixture for constant pressure flow measurement standard equipment, 21-1, temperature sensor, 21-2, temperature sensor, 22, front-end measurement working solenoid valve, 23, front-end measurement isolation solenoid valve, 24, back-end measurement isolation solenoid valve, 25, Solenoid valve for back-end measurement work, 26, flow meter, 27, front-end measurement ventilation solenoid valve, 28, back-end measurement ventilation solenoid valve, 29, differential pressure sensor, 30, pressure sensor, 31, mode conversion switch, 32, solenoid valve Controller, 33, sensor data collector.

In the figure: ┄┄┄air connection, ───electrical connection.

detailed description

The utility model is further described below in conjunction with accompanying drawing:

As shown in Figure 1: a measuring device for standard appliance verification that can control the airflow source, including a linear suction system, a measurement and test system, and a control system for controlling the suction system and the measurement and test system, wherein: the measurement and test The system includes a constant pressure flow measurement unit used to verify the standard utensils of cigarette standard rods and ventilation rate standard rods, and a constant current pressure measurement unit used to verify the standard utensils of air permeability of cigarette paper. The two units are connected in parallel. Installed on the working interface (15) at the air outlet at the front end of the piston cylinder in the linear suction system, and the test mode switching between the two units is controlled by the mode switching switch (31) set in the control system;

The linear suction system consists of a suction piston (14), a lead screw (5) connected to the piston rod (13), and a servo motor (11) that drives the lead screw to rotate. The rotation of the servo motor and the movement interval of the piston rod The limit switches (2, 3) are all controlled by the control system (1);

The constant pressure flow measurement unit includes a working interface (15), a working solenoid valve (16), working solenoid valves (22, 25) for front and rear end measurement, front and rear end measurement isolation solenoid valves (23, 24), flow Gauge 26, constant pressure flow measurement standard fixture fixture (20-2), fixture front interface (19-2) and the pressure difference sensor (29) set at the inlet end of the fixture, the temperature inside the fixture Sensors (21-2), all solenoid valves, differential pressure sensors 29 and temperature sensors (21-2) in the unit are electrically connected to the control system (1); the flowmeter (26) can be a mass flowmeter, It can also be a volume flow meter.

The constant current pressure measurement unit includes a working interface (15), a working solenoid valve (16), a constant current pressure measurement standard instrument clamp (20-1), a front interface of the clamp (19-1) and a The pressure sensor (30) at the intake end, the temperature sensor (21-1) located in the fixture, the working solenoid valve in the unit, the pressure sensor (3) and the temperature sensor (21-1) are all connected with the control system ( 1) electrical connection;

An air path leading to the atmosphere is also provided on the working interface (15), and a return electromagnetic valve (17) and a noise-eliminating filter (18) are installed on the air path.

In the utility model, the lead screw (5) and the servo motor (11) in the linear suction system are connected through a coupling (10), and the front and rear ends of the lead screw (5) are installed with Front and rear end limit switches (2, 3).

When the utility model is in use, it is divided into two situations of "constant pressure flow measurement" and "constant current pressure measurement":

Implementation Mode 1: "Constant pressure flow measurement" mode

Now in conjunction with FIG. 1 , the implementation process of the constant pressure side flow of the present invention is described as follows: on the controller 1, the mode of "constant pressure flow measurement" is selected through the constant pressure side flow/constant current pressure measurement mode switch 31. At this time, the control system of the device (1), front and rear limit switches (2, 3), lead screw (5), coupling (10), servo motor (11), piston cylinder (12), piston Rod (13), piston (14), working port (15), working solenoid valve (16), return solenoid valve (17), muffler filter (18), fixture front port (19-2), standard appliance Fixture (20-2), temperature sensor (21-2), front-end measurement solenoid valve (22), front-end measurement isolation solenoid valve (23), rear-end measurement isolation solenoid valve (24), rear-end measurement solenoid valve (25), flow meter (26), front-end measurement ventilation solenoid valve (27), back-end measurement ventilation solenoid valve (28), differential pressure sensor 29, etc. form a "constant pressure flow measurement" mode.

The control system (1) sends instructions according to the feedback signals of the gas temperature and pressure sensors in various parts, through compensation calculations, and according to the set technical index requirements, and the piston suction driven by the servo motor (11) is set: the device under test (20 -2) Pressure difference index condition, the piston changes the air flow in the gas path through speed regulation, and then causes the pressure change of the tested appliance (20-2), when the pressure difference of the tested appliance (20-2) reaches the set condition, The pressure is kept constant, and the movement speed of the piston is locked, thereby forming a stable air flow; according to measurement requirements, the flow meter (26) of the flow test unit in the gas path is selected to measure the gas flow.

Implementation mode 2: "Constant current pressure measurement" mode

On the controller 1, select the "constant current pressure measurement" mode through the constant voltage side flow/constant current pressure measurement mode switch (31). At this time, the control system of the device (1), the front and rear limit switches (2, 3), the lead screw (5), the coupling (10), the servo motor (11), the piston cylinder (12), the piston Rod (13), piston (14), working port (15), working solenoid valve (16), return solenoid valve (17), muffler filter (18), fixture front port (19-1), standard appliance The fixture (20-1), temperature sensor (21-1), pressure sensor 30, etc. form a "constant current pressure measurement" mode.

Use this device to verify the standard stick of cigarette-shaped draw resistance, insert the standard stick of smoke-shaped draw resistance into the test fixture (20-1), and set the theoretical flow value of the working air flow, standard temperature value, and ambient atmospheric pressure specified in the verification measurement value, start the device on the controller (1), the controller (1) is based on the set working air flow theoretical flow value, temperature value, standard atmospheric pressure value and the actual temperature value measured by the temperature sensor (21-1), ambient atmospheric pressure The actual flow value of the working air flow is calculated by the principle of aerohydrodynamics and the formula, and the controller (1) controls the speed of the servo motor (11) according to the value to obtain the corresponding flow value of the working air flow. (16) Open, the return solenoid valve (17) is closed, read the value of the pressure sensor 30 after stabilization, which is the suction resistance value of the cigarette-shaped suction resistance standard rod, and the piston moves to the rear limit switch (3) to enter During the return stroke, the working solenoid valve (16) is closed, and the return solenoid valve (17) is opened until the piston stops after the front end limit switch (2), and the device is to be tested for the next round of test work.

Claims (4)

1. A measuring device for standard appliance verification that can control the airflow source, comprising a linear suction system, a measurement test system and a control system for controlling the suction system and the measurement test system, characterized in that: the measurement test system includes The constant pressure flow measurement unit used to verify the standard appliance of cigarette standard rod and ventilation rate standard rod, and the constant current pressure measurement unit used to verify the standard appliance of cigarette paper air permeability, the two units are connected in parallel and installed on On the working interface at the air outlet at the front end of the piston cylinder in the linear suction system, and the test mode conversion between the two units is controlled by the mode conversion switch set in the control system; The linear suction system is composed of a suction piston, a screw connected to the piston rod, and a servo motor that drives the screw to rotate, and the rotation of the servo motor and the limit switch in the movement range of the piston rod are controlled by the control system; The constant pressure flow measurement unit includes a working interface, a working solenoid valve, a working solenoid valve for front and rear end measurement, a front and rear end isolation solenoid valve, a flow meter, a fixture for constant pressure flow measurement standard equipment, a front interface of the fixture, and a The differential pressure sensor at the intake end, the temperature sensor set in the fixture, all the solenoid valves, differential pressure sensors and temperature sensors in the unit are electrically connected to the control system; The constant current pressure measurement unit includes a working interface, a working solenoid valve, a constant current pressure measurement standard fixture fixture, a front interface of the fixture, a pressure sensor arranged at the inlet end of the fixture, and a temperature sensor arranged in the fixture, The working solenoid valve, pressure sensor and temperature sensor in the unit are all electrically connected with the control system; An air path leading to the atmosphere is also provided on the working interface, and a return solenoid valve and a noise reduction filter are installed on the air path. 2 . The measuring device for standard instrument verification with controllable airflow source according to claim 1 , characterized in that: the screw and the servo motor in the linear suction system are connected through a coupling. 3 . 3. The measuring device for standard appliance verification with controllable airflow source according to claim 1 or 2, characterized in that front and rear limit switches are installed at the front and rear ends of the lead screw. 4 . The measuring device for standard instrument verification with controllable airflow source according to claim 1 , characterized in that: the flowmeter in the constant pressure flowmeter is a mass flowmeter or a volume flowmeter.