RU216184U1 - Device for automated selection and transfer of substances from the phase boundary - Google Patents

Abstract

The device belongs to the field of instrumentation, in particular general laboratory instruments that provide sampling for further measurement of the composition and physico-chemical properties of substances.

The device for automated selection and transfer of substances from the liquid-gas and solid-gas interface to the probe surface contains a level-adjustable platform with a thermal table. A linear movement axis is fixed vertically to the platform, on which a movable carriage with a holder is placed. The movement of the carriage is controlled by a stepper motor with a driver. Limit switches are provided to determine the extreme positions. The device also contains a microcontroller configured to generate control pulses for the stepper motor driver, which has a step divider to change the number of steps per revolution of the axis. The holder is made with the possibility of replacing the probe with a suitable geometry and material.

The technical result consists in the possibility of automation of the sampling process, high-precision control of the movement of the probe and the quantitative transfer of the substance from the interface to the surface of the probe. 2 ill.

Description

The utility model relates to the field of instrumentation, in particular general laboratory instruments that provide sampling for further measurement of the composition and physico-chemical properties of substances.

From the prior art, a sampler is known for assessing the thickness of the oil layer above water (RF Patent No. 2534791, priority date 12/10/2014), containing a thin-walled, transparent vertical body made of a material that is not wetted by oil and oil products. The body without a bottom has an internal cross-sectional area that is constant in height and a sharp edge in the lower part; in the upper part, the body is tapered and connected to a flexible outlet, to which two taps are connected: a side valve for passing air and a central one for passing liquids, to the central one a calibrated pipette is attached to the tap, which in turn is connected to a double-acting pump. The calibrated pipette is configured to pre-place a fixed volume of oil solvent and then pump the solvent into the oil. The sampler body is superior to a calibrated pipette in terms of internal cross-sectional area. A disadvantage of the known sampler is the small amount of the sample taken, due to the execution of the sampler body from a non-wettable material, which does not allow for a slow runoff of the sample and, as a result, the formation of an oil film on the surface of the sampler in sufficient quantity.

Also known is a sampler for taking films of oil and oil products from the water surface (RF patent No. 2679232, priority date 06.12.2017), made in the form of a hollow cylinder made of inert material, on the outer surface of which there are risks for measuring the volume of the sample taken, and two covers made of inert material. One of them can be installed at the end of the cylinder on the side of sampling from the water surface, and the other - at the second end of the sampler cylinder. Before sampling the films, the narrow section of the sampler is annealed in an oven. Next, the sampler is cooled to ambient temperature. For sampling, the sampler is placed with a wide area above the liquid with a film in the container. Then the sampler is quickly lowered vertically down into the water with a film of oil and oil products on the surface. The disadvantages of this device is the inability to control the speed of movement, the angle and depth of the probe, since all manipulations are carried out manually. Another disadvantage is the additional steps of heating and cooling the device element.

There is a known patent (US 2003OO77396A1, priority date 10/22/2002) describing a device for applying coatings by immersion (dip-coating), the design has a submersible tank, a capture and hold mechanism, sensors for controlling the immersion area and a mechanism for moving the substrate. The substrate is immersed in a reservoir of liquid substance using an automatic system, the substance is fixed on the surface of the substrate, the sample is removed and used for further coating steps. The disadvantage of the installation is the use of only flat substrates, the absence of temperature control of the sample, the applicability only for creating coatings, and the impossibility of using it for sampling.

The closest to the proposed technical solution is the patent "Method for the selection of films of oil and oil products from the surface of the water and a device for its implementation" (RF Patent No. 2604843C1, priority date 13.05.2015). The technical problem solved in the proposed solution (method and device) is to increase the accuracy of the analysis, the possibility of quantitative analysis of organic substances in the selected sample, as well as the possibility of sampling for analysis in the field. The device is made in the form of a hollow cylinder with a stopper made of an inert material and a tip, in which a precision valve is installed. The sampler has a developed inner surface. On the outer surface of the sampler, there are marks for measuring the volume of the sample being taken. Before sampling, the sampler is annealed and then cooled to ambient temperature and lowered into the test sample. Take a fixed volume of the sample. Then slowly drain the aqueous phase and analyze the film deposited on the inner surface of a known area of the sampler for the content of organic matter. The main disadvantages of this sampler are the need to manually close the valve and manually move the sampler, which reduces the reproducibility and accuracy of sampling, the need for annealing and a limited scope (only for oil and oil products).

The purpose of the proposed device is to automate sampling from the liquid-gas and solid-gas interface, and transfer the sample to the probe for further research.

This goal is achieved by using a fixed probe with suitable geometry and material in a holder on a movable carriage placed on a linear axis with a stepper motor, while the axis is mounted vertically to a platform equipped with a thermal table, and a stepper motor driver is installed and fixed on top of the motor, which has step divider for changing the number of steps per revolution of the axis, which controls the movement, while the control signals to the thermal table and the stepper motor driver are supplied using microcontrollers attached to the device.

The advantage of this device is the use of a fixed probe with suitable geometry and material in a holder on a movable carriage placed on a linear axis with a stepper motor, high-precision control of the probe movement due to the microcontroller responsible for generating control pulses for the stepper motor driver, which has a step divider to change the number of steps per axis revolution.

The technical result consists in the possibility of automating the sampling process, high-precision control of the movement of the probe and the quantitative transfer of matter from the phase boundary to the surface of the probe through the use of a fixed probe with suitable geometry and material in a holder on a movable carriage placed on a linear movement axis with a stepper motor; microcontroller responsible for generating control pulses for the stepper motor driver, which has a step divider to change the number of steps per revolution of the axis.

The essence of the device is illustrated by drawings, where figure 1 shows a diagram of a device ready for operation, and figure 2 shows a block diagram of the installation.

The essence of the device is illustrated by drawings, where figure 1 shows a diagram of a device ready for operation, and figure 2 shows a block diagram of the installation.

The overall dimensions of the installation are 500x330x710 mm. In Fig.1. the unit is shown on an aluminum platform 500x330x16 mm (1) with legs. A linear movement axis (2) with a stepper motor (3) is vertically mounted on the platform, which is attached to the platform by 4 steel corners (4). A stepper motor driver is mounted on top of the motor. A carriage (5) with a plate (6) for fastening the chemical foot is installed on the axis. The carriage travel along the vertical axis is 500 mm. There are 3 limit switches (7) on the axis to determine the extreme and intermediate positions of the carriage. A thermal table (8) is installed and fixed on the platform for thermal stabilization of the sample collection container.

The AC/DC ~ 220 - 24V power supply is installed and fixed in the 19-inch 4U board mounting block (cradle). The power supply of the unit is 24V and the signals from the microcontrollers fixed on the crate are transmitted from the crate via a cable to the stepper motor driver and to the thermal table fixed on the platform. Two microcontrollers are installed in the crate to generate control pulses. One microcontroller is responsible for processing signals from limit switches, an emergency stop button and generating control pulses for a stepper motor driver. The stepper motor driver has a step divider to change the number of steps per revolution. The second microcontroller is responsible for thermal stabilization of the sample. It receives data from a digital temperature sensor installed at the bottom of the heating table. Based on the received temperature, power is supplied to the contacts of the heating table heater or it is turned off.

The installation works as follows. The test sample containing the phase boundary is placed on a thermal table that maintains a given temperature. Using the software, the parameters of movement of a probe fixed on a carriage with a certain geometry are set: movement distance, movement time and duration of exposure of the probe in the sample, linear coordinates, heating temperature. Next, from the software application, the operation of the installation is started. The probe takes samples and the substance is transferred to the surface. Then the selected sample of the substance is used for further stages of the study.

Thus, the described installation allows automated sampling at the phase boundary.

Claims (1)

A device for automated selection and transfer of substances from the liquid-gas and solid-gas interface to the probe surface, containing a platform with level control, a linear movement axis fixed vertically to the platform with a thermal table, a holder on a movable carriage located on the linear movement axis , characterized in that it has a stepper motor, limit switches for determining extreme positions, a stepper motor driver and a microcontroller configured to generate control pulses for the stepper motor driver, which has a step divider to change the number of steps per revolution of the axis; the holder is configured to replace the probe with a suitable geometry and material.

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