Automatic suction resistance calibration device for filter stick cigarette comprehensive test board

Abstract

The invention relates to an automatic suction resistance calibration device for a filter stick cigarette comprehensive test board, which comprises a self-calibration mechanism, a measuring cylinder, a filtering device, a negative pressure generator, a precise differential pressure sensor and a measuring loop control system, and is characterized in that the self-calibration mechanism consists of a built-in calibration stick shell, a built-in pipe sleeve, an extension pipe, an O-shaped sealing ring, a balance pipeline, a negative pressure pipeline and a measuring pipeline; according to the invention, the initial position of the measuring cylinder is automatically calibrated through the self-calibration mechanism, timing automatic calibration without shutdown is realized, the operation is simple and convenient, and the effectiveness of the detection precision of the instrument suction resistance measuring module is ensured, so that the accuracy and the stability of online detection data of a product are ensured; the influence of human factors on the measurement result is eliminated, and the measurement precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of measuring the draw resistance of cigarette filter rods, and particularly to an automatic calibration device for the draw resistance of a comprehensive test bench for filter rods and cigarettes. Background Art

[0002] In the tobacco industry, important indicators required to be inspected in the physical properties of cigarettes and filter rods are important technical indicators for standardizing cigarette production. During the production process, strict detection is required for relevant technical indicators. The on-line comprehensive test bench used for detection needs to test cigarettes and filter rods one by one, and draw resistance is an important item among the important indicators. In order to ensure the continuity of the test and the accuracy of the test data, a device is needed to automatically calibrate the draw resistance.

[0003] The existing calibration method uses manual timing calibration. During calibration, the machine needs to be stopped for calibration. The standard rod is placed in the measuring cylinder for measurement and calibration. The uncontrollable factors in manual calibration are relatively large. The ambient temperature of the standard rod storage environment and the measuring unit are inconsistent, which is also likely to cause measurement and calibration errors.

[0004] An important indicator affecting the accuracy of draw resistance measurement data is the ambient gas temperature. When the ambient temperature increases by one degree, the draw resistance data can increase by about 20 Pa. In order to ensure the accuracy of automatic calibration, a device needs to be designed to ensure that the internal and external ambient temperatures of the standard rod are consistent. And this device can ensure the accuracy of calibration and measurement by ensuring that the ambient air circulation temperature of the standard rod is consistent with the measurement ambient temperature.

[0005] Both CN200710157563.1 and CN200720015396.2 disclose an automatic calibration system for a draw resistance meter, both of which involve an "automatic calibration system for a draw resistance meter, having a gas circuit device and an electric control device. The gas circuit device includes a calibration gas circuit and a measurement gas circuit, which are connected in parallel to the same gas source. The calibration gas circuit has two draw resistance standard rod measurement heads, and the measurement gas circuit has a sample measurement head. Each measurement head in its respective gas circuit is respectively connected to a negative pressure vacuum pump through an electric valve and a manual valve, and then through the same flow constant element and a buffer chamber. A gas pressure difference sensor is provided in the flow constant element and the buffer chamber"; although the automatic calibration of the standard rod is disclosed, neither of them considers the air flow balance problem of the standard rod. Since temperature has a great influence on draw resistance, if the ambient temperature of the standard rod and the ambient temperature of the measuring cylinder are inconsistent, a large measurement error will occur. Summary of the Invention

[0006] The object of the present invention is to provide an automatic suction resistance calibration device for a comprehensive filter rod and cigarette testing bench, which can replace manual operation for the suction resistance self-calibration function, perform calibration without stopping the machine according to the set time, and ensure that the ambient temperature of the standard rod is the same as the measurement environment, thereby improving the measurement accuracy, reducing the operation complexity, and ensuring the accuracy and stability of the data.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An automatic suction resistance calibration device for a comprehensive filter rod and cigarette testing bench includes a self-calibration mechanism, a measuring cylinder, a filtering device, a negative pressure generator, a precision differential pressure sensor, and a measurement loop control system. Among them, the self-calibration mechanism is used to automatically calibrate the initial position of the measuring cylinder. The measuring cylinder is used for measuring cigarette rods or filter rods, or for calibrating the suction resistance during manual calibration. The filtering device is located at the inlet of the measuring cylinder and is used to filter out impurities in the fluid or gas to be measured. The negative pressure generator is located at the frontmost part of the entire device and is used to provide the negative pressure required for the test of the device, so as to ensure that the stable gas source of the measurement system enters the measuring cylinder or the self-calibration mechanism for operation, and is used to detect the differential pressure in the measuring cylinder or the differential pressure of the standard rod in the self-calibration mechanism. The measurement loop control system is used to control the gas path switching of the entire measurement system and control the operation of the negative pressure generator to achieve self-calibration and precise measurement.

[0009] Preferably, the self-calibration mechanism is composed of an internal calibration rod housing, an internal pipe sleeve, an extension pipe, an O-ring, a balance pipeline, a negative pressure pipeline, and a measurement pipeline. A standard rod can be placed inside the internal pipe sleeve.

[0010] Preferably, the pipe sleeve where the standard rod is placed and the balance pipeline are communicated with the atmosphere to balance the temperature difference inside and outside the internal pipe sleeve, ensure that the temperature of the standard rod is the same as the external environment temperature, and eliminate calibration errors.

[0011] Preferably, the self-calibration mechanism is arranged in parallel with the measuring cylinder. The self-calibration mechanism and the measuring cylinder are connected in parallel through a gas path pipeline at the measurement loop control system. The measurement system pipeline is switched through the measurement loop control system to control the separate measurement of the self-calibration mechanism and the measuring cylinder.

[0012] Preferably, the precision differential pressure sensor is located at the parallel position of the measuring cylinder and the self-calibration mechanism.

[0013] The beneficial effects of the present invention:

[0014] 1) The present invention automatically calibrates the initial position of the measuring cylinder through the self-calibration mechanism, realizes the timed automatic calibration without stopping the machine, is simple and convenient to operate, ensures the detection accuracy and effectiveness of the suction resistance measurement module of the instrument, further ensures the accuracy and stability of the online detection data of the product, eliminates the influence of human factors on the measurement results, and improves the measurement accuracy;

[0015] 2) The present invention keeps the ambient temperature of the standard rod consistent with the ambient temperature where the measuring cylinder is located, avoiding calibration errors caused by temperature difference effects, and ensuring the stability and accuracy of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of an automatic suction resistance calibration device for a comprehensive filter rod and cigarette test bench according to the present invention.

[0017] Figure 2 is a schematic structural diagram of the self-calibration mechanism of the present invention.

[0018] Figure 3 is a schematic system diagram of an automatic suction resistance calibration device for a comprehensive filter rod and cigarette test bench according to the present invention.

[0019] In the figure: 1. Self-calibration mechanism, 101. Negative pressure pipeline, 102. O-ring seal, 103. Measuring pipeline, 104. Balance pipeline, 105. Extension pipe, 106. Standard rod, 107. Inner calibration rod housing, 108. Inner pipe sleeve; 2. Measuring cylinder; 3. Filter device; 4. Negative pressure generator; 5. Precision differential pressure sensor; 6. Measuring circuit control system. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the accompanying drawings, but the present invention is not limited to these embodiments.

[0021] As Figure 1 shown, an automatic suction resistance calibration device for a comprehensive filter rod and cigarette test bench includes a self-calibration mechanism 1, a measuring cylinder 2, a filter device 3, a negative pressure generator 4, a precision differential pressure sensor 5, and a measuring circuit control system 6. Among them, the self-calibration mechanism 1 is used to automatically calibrate the initial position of the measuring cylinder 2. The measuring cylinder 2 is used for measuring cigarette rods or filter rods, or for calibrating the suction resistance during manual calibration. The filter device 3 is located at the entrance of the measuring cylinder 2 and is used to filter out impurities in the fluid or gas to be measured. The negative pressure generator 4 is located at the frontmost part of the entire device. The negative pressure generator 4 is used to provide the negative pressure required for the test of this device, so as to ensure that a stable air source of the measurement system enters the measuring cylinder 2 or the self-calibration mechanism 1 for operation, and is used to detect the differential pressure in the measuring cylinder 2 or the differential pressure of the standard rod 106 in the self-calibration mechanism 1. The measuring circuit control system 6 is used to control the air path switching of the entire measurement system and control the operation of the negative pressure generator 4 to achieve self-calibration and precise measurement.

[0022] The self-calibration mechanism 1 is composed of an internal calibration rod housing 107, an internal tube sleeve 108, an extension tube 105, an O-ring 102, a balance pipeline 104, a negative pressure pipeline 101, and a measurement pipeline 103. A standard rod 106 can be placed inside the internal tube sleeve 108.

[0023] For the tube sleeve where the standard rod 106 is placed, the balance pipeline 104 is connected to the atmosphere, thereby balancing the temperature difference inside and outside the internal tube sleeve 108, ensuring that the temperature of the standard rod 106 is consistent with the external environment temperature, and eliminating calibration errors.

[0024] The self-calibration mechanism 1 and the measurement cylinder 2 are parallel devices.

[0025] The precision differential pressure sensor 5 is located at the parallel connection of the measurement cylinder 2 and the self-calibration mechanism 1.

[0026] The working principle of the present invention:

[0027] According to the process requirements, the measurement pipeline 103 and the calibration pipeline can be switched through the measurement loop control system 6 at regular intervals. When the comprehensive test bench is working normally, the measurement loop control system 6 is started, and the working position of the negative pressure generator 4 is switched to the self-calibration mechanism 1. The measurement loop control system 6 opens the measurement pipeline 103. At this time, the calibration pipeline is in a closed state, and the cigarette rod / filter rod placed in the measurement cylinder 2 is measured. The draw resistance data is obtained by measuring the pressure difference at both ends of the cigarette rod or filter rod. The pressure difference at both ends of the measurement cylinder 2 or the automatic calibration device is read by the precision differential pressure sensor 5, and the data is processed by the measurement loop control system 6. When calibration is required, the measurement loop control system 6 automatically switches to open the calibration pipeline to measure the internal standard rod 106. At this time, the measurement pipeline 103 is in a closed state, and then the negative pressure generator 4 is started. The negative pressure gas enters the self-calibration mechanism 1, and the standard rod 106 is placed inside the self-calibration mechanism 1. The pressure difference value of the standard rod 106 inside the self-calibration mechanism 1 is measured by the precision differential pressure sensor 5. The tube sleeve where the standard rod 106 is placed, the balance pipeline 104 is connected to the atmosphere, which can balance the temperature difference inside and outside the tube sleeve, ensure that the temperature of the standard rod 106 is consistent with the external environment temperature, and eliminate calibration errors to achieve accurate measurement; at the same time, under the control of the program, the gas path is connected to the measurement cylinder 2 for measuring the cigarette rod or filter rod during normal measurement. Through regular calibration of the draw resistance, at this time, the gas path is switched to the self-calibration mechanism 1, and the precision differential pressure sensor 5 reads the pressure difference data of the standard rod 106. After the data is processed, the draw resistance data is calibrated.

[0028] The present invention uses gas path switching to ensure the measurement and calibration states. The pressure difference between the two ends of the measurement cylinder 2 or the self-calibration mechanism 1 is read out by the precision differential pressure sensor 5. The pressure difference is the suction resistance data, which is processed by the measurement loop control system 6. In the space for placing the standard rod 106 shown in the figure, the negative pressure loop is connected to the precision differential pressure sensor 5 for data reading, while the balance pipeline 104 is connected to the atmospheric positive pressure, which is the same as the environment where the measurement cylinder 2 is located. The standard rod 106 in the self-calibration mechanism 1 is in a balanced environment, which can separate the negative pressure during measurement from the positive pressure environment of the standard rod 106, eliminating the calibration error caused by temperature differences and ensuring the consistency of data.

[0029] Meanwhile, the present invention automatically calibrates the initial position of the measurement cylinder 2 through the self-calibration mechanism 1, realizing the timed automatic calibration without stopping the machine. The operation is simple and convenient, ensuring the effectiveness of the detection accuracy of the suction resistance measurement module of the instrument, and further guaranteeing the accuracy and stability of the on-line detection data of the product, eliminating the influence of human factors on the measurement results, improving the measurement accuracy, and ensuring the stability and accuracy of the measurement.

[0030] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An automatic calibration device for the draw resistance of a filter rod cigarette comprehensive test bench, characterized in that: It comprises a self-calibration mechanism (1), a measuring cylinder (2), a filtering device (3), a negative pressure generator (4), a precision differential pressure sensor (5) and a measuring loop control system (6); wherein: The self-calibration mechanism (1) is used to automatically calibrate the initial position of the measuring cylinder (2), and the measuring cylinder (2) is used to measure cigarettes or filter rods, or to calibrate the draw resistance when manual calibration is required; The filter device (3) is located at the inlet of the measuring cylinder (2) and is used to filter out impurities in the fluid or gas to be measured; The negative pressure generator (4) is located at the front of the entire device and is used to provide the negative pressure required for the device test, thereby ensuring that a stable gas source of the measuring system enters the measuring cylinder (2) or the self-calibration mechanism (1) to work, forming a pressure difference in the measuring cylinder (2) or a pressure difference of the standard rod (106) in the self-calibration mechanism (1); The measurement loop control system (6) is used to control the gas path switching of the entire measurement system and control the operation of the negative pressure generator (4) to achieve self-calibration and accurate measurement; The self-calibration mechanism (1) and the measuring cylinder (2) are arranged in parallel; the self-calibration mechanism (1) and the measuring cylinder (2) are connected in parallel at a measuring loop control system (6) through an air pipeline, and the measuring loop control system (6) switches the measuring system pipeline to control the self-calibration mechanism (1) and the measuring cylinder (3) to measure separately.

2. The automatic calibration device for the draw resistance of a filter rod cigarette comprehensive test bench according to claim 1, characterized in that: The self-calibration mechanism (1) is composed of a built-in calibration rod housing (107), a built-in pipe sleeve (108), a built-in standard rod (106), an extension tube (105), an O-ring (102), a balance pipeline (104), a negative pressure pipeline (101) and a measuring pipeline (103); the built-in standard rod (106) is placed inside the built-in calibration rod housing (107) through the built-in pipe sleeve (108); the extension tube (105) is connected to the built-in calibration rod housing (107) to form a built-in standard rod. The extended measuring pipeline of the calibration rod (106) and the balancing pipeline (104) are connected to the negative pressure air source: the indoor air enters the outside of the built-in standard rod (106) through the side hole of the built-in calibration rod shell (107) through the negative pressure, and then flows out through the outer wall of the extension pipe (105) and the balancing pipeline (104), thereby achieving the effect of balancing the built-in standard rod and the indoor atmospheric temperature. The negative pressure pipeline (101) is connected to the measurement loop control system (6), and the measuring pipeline (103) is connected to the precision differential pressure sensor (5).

3. The automatic calibration device for the draw resistance of the filter rod cigarette comprehensive test bench according to claim 2, characterized in that: The pipe sleeve and the balance pipe (104) in which the standard rod (106) is placed are connected to the atmosphere and are used to balance the temperature difference between the inside and outside of the built-in pipe sleeve (108) and ensure that the temperature of the standard rod (106) is consistent with the external environment temperature.

4. The automatic calibration device for draw resistance of filter rod cigarette comprehensive test bench according to claim 1, characterized in that: The precise differential pressure sensor (5) is located at the parallel connection between the measuring cylinder (2) and the self-calibration mechanism (1).

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