Microwave detection device module for double-channel cigarette production equipment

Abstract

This invention belongs to the field of cigarette testing technology, and particularly relates to a microwave detection device module for dual-channel cigarette production equipment. It includes two interconnected device units, each equipped with a detection section and a cigarette channel. The detection section includes a microwave generating module, a detector module, and a resonant cavity. The cigarette channel forms an annular notch inside the resonant cavity. A first waveguide ring and a second waveguide ring are located on either side of the annular notch. A signal-converging inclined surface is located at the end of the first and second waveguide rings near the annular notch, forming an angle greater than 90° and less than 180° with the cigarette channel to enhance the electric field strength of the microwave signal within the annular notch. This invention reduces the volume of the resonant cavity while ensuring detection accuracy by increasing the electric field strength generated by the resonant cavity and reducing losses. This allows the two device units to be assembled side-by-side, compatible with single-channel and dual-channel cigarette production equipment, and reduces the height and overall size of the microwave detection device.

Description

Technical Field

[0001] This invention belongs to the field of cigarette testing technology, and in particular relates to a microwave testing device module for dual-channel cigarette production equipment. Background Technology

[0002] In the cigarette manufacturing industry, the density and humidity of cigarettes largely determine the product quality. Therefore, it is necessary to continuously measure and adjust the density and humidity of cigarettes during the production process. The function of the microwave online cigarette density and humidity testing device is to quickly and accurately measure the density and humidity of cigarettes and feed the data back to the control system of the production equipment, so that the control system can complete the automated control.

[0003] Dual-channel cigarette production equipment integrates two high-speed automatic cigarette systems into a single production unit, creating two cigarette packs during production and increasing cigarette production capacity. To continuously and accurately test the density and moisture content of each cigarette pack, each pack must pass through a resonant cavity in its respective testing device. However, in most dual-channel cigarette production equipment in the industry, the axial distance between the two cigarette pack channels is only 38mm. Due to volume constraints, the two resonant cavities cannot be placed side-by-side. Reducing the volume of the resonant cavities would increase their resonant frequency, decrease the electric field strength generated, and consequently reduce the penetration depth of the electric field in the cigarette pack. This could lead to insensitivity to the center density of the cigarette pack during measurement, resulting in significant measurement errors and ultimately affecting the quality of the cigarettes.

[0004] In response, most microwave detection devices on the market for dual-channel cigarette production equipment consist of two staggered resonant cavities. This necessitates extending the length of the cigarette channel within the device, inevitably increasing its height and overall size. To detect the density and moisture content of cigarette strips in both single-channel and dual-channel production equipment, manufacturers must design two different detection systems and provide maintenance and technical support for both, increasing product development complexity and maintenance costs. Furthermore, cigarette factories also need to equip themselves with spare parts for both single-channel and dual-channel microwave detection systems, resulting in additional equipment expenses.

[0005] Therefore, there is an urgent need for a microwave detection device module for dual-channel cigarette production equipment that can reduce the volume of the resonant cavity to decrease the height and overall size of the device while ensuring detection accuracy, and is compatible with single-channel cigarette production equipment. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a microwave detection device module for dual-channel cigarette production equipment. This module can reduce the volume of the resonant cavity while ensuring detection accuracy by increasing the electric field strength generated by the resonant cavity and reducing losses. This allows two individual devices to be assembled side by side, making it compatible with single-channel and dual-channel cigarette production equipment. It also reduces the height and overall volume of the microwave detection device module, thereby lowering the development difficulty and maintenance costs of the device.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A microwave detection device module for a dual-channel cigarette production equipment includes:

[0009] Two connected unit devices, each unit having a cigarette channel that runs through it, and each unit having a detection unit for detecting cigarette density and humidity.

[0010] The detection unit includes a microwave generating module and a detector module connected to the microwave generating module, as well as a resonant cavity connected to the detector module through a signal input terminal and a signal output terminal. The cigarette channel passes through the resonant cavity and forms an annular notch inside the resonant cavity. The resonant cavity has a first waveguide ring and a second waveguide ring on both sides of the annular notch, which are annularly fitted to the outer wall of the cigarette channel. The distance between the first waveguide ring and the second waveguide ring is equal to the width of the annular notch. When the cigarette is located in the cigarette channel, the microwave signal entering the resonant cavity through the signal input terminal will penetrate the cigarette located in the annular notch and be output to the detector module through the signal output terminal.

[0011] The first waveguide ring and the second waveguide ring are provided with a signal focusing slope around one end near the annular notch. The signal focusing slope forms an angle greater than 90° and less than 180° with the cigarette channel, which is used to enhance the electric field strength of the microwave signal in the annular notch.

[0012] Furthermore, the resonant cavity includes an annular cover and a flange that cooperate to form an annular chamber, with the first waveguide ring disposed on the annular cover and the second waveguide ring disposed on the flange.

[0013] Furthermore, both the signal input terminal and the signal output terminal are disposed on the annular cover, and an impedance matching ring is also disposed on the flange. The impedance matching ring is disposed between the second waveguide ring and the side wall of the annular cavity and is coaxial with the second waveguide ring. The impedance matching ring is used to make the impedance of the resonant cavity close to 50 ohms.

[0014] Furthermore, the impedance matching ring extends on the flange toward the inner end face of the annular cover and does not exceed the height of the second waveguide ring.

[0015] Furthermore, the diameter of the impedance matching ring is the midpoint between the outer diameter of the second waveguide ring and the inner diameter of the annular cavity, so that the distance between the impedance matching ring and the second waveguide ring is equal to the distance between the impedance matching ring and the inner wall of the annular cavity.

[0016] Furthermore, the signal input terminal includes a first signal needle, and the signal output terminal includes a second signal needle. Both the first signal needle and the second signal needle pass through the annular cover and extend into the annular chamber, and are equidistantly positioned on both sides of the cigarette channel.

[0017] Preferably, the angle between the signal focusing slope and the cigarette channel is 135°.

[0018] Furthermore, the microwave generating module and the detector module are connected by a microwave conduit, and the microwave conduit is provided with a third signal pin that is respectively connected to the microwave generating module and the detector module, for transmitting the signal emitted by the microwave generating module to the detector module.

[0019] Furthermore, the device unit also includes a processing module sleeved on the outside of the detection unit and electrically connected thereto. The processing module is used to control the detection unit to perform corresponding test actions and to collect and process the signal data output by the detection unit.

[0020] Furthermore, the cigarette channel is located near the center of one of the edges of the device unit, and the axial distance between the cigarette channels of the two connected device units is 38mm.

[0021] The beneficial effects of this invention are:

[0022] This invention utilizes two interconnected device units. A single unit can be used in a single-channel cigarette production equipment, while the two connected units can be used in a dual-channel cigarette production equipment. By placing a first waveguide ring and a second waveguide ring on both sides of the annular notch in the resonant cavity of each device unit, and by surrounding the ends of the first and second waveguide rings near the annular notch with a signal-converging inclined surface, the electric field strength of the microwave signal in the annular notch is enhanced, allowing for reduced resonant cavity volume while maintaining detection accuracy. By placing an impedance matching ring coaxial with the second waveguide ring on the flange of the resonant cavity, with its height not exceeding that of the second waveguide ring, the impedance of the resonant cavity is made close to 50 ohms to minimize reflection loss. By setting the diameter of the impedance matching ring to the midpoint between the outer diameter of the second waveguide ring and the inner diameter of the annular cavity, a portion of the resonant cavity is divided into two equal-width secondary cavities using the impedance matching ring. The microwaves travel similar distances in the two sub-cavities, thus reducing mutual interference and losses during reflection. A microwave conduit connects the microwave generator and detector modules, facilitating signal transmission. A processing module controls the detection unit to perform corresponding tests and collects and processes the output signal data. The axial spacing of the cigarette channels in the two connected units is set to 38mm, making it suitable for common dual-channel cigarette production equipment. This invention reduces the resonant cavity volume while maintaining detection accuracy by increasing the electric field strength and reducing losses. This allows the two units to be assembled side-by-side, compatible with both single-channel and dual-channel cigarette production equipment, reducing the height and overall size of the microwave detection module, and lowering development and maintenance costs. Attached Figure Description

[0023] Appendix Figure 1 This is an exploded structural diagram of a single device unit of the present invention;

[0024] Appendix Figure 2 This is a schematic diagram of the structure of the microwave detection device module of the present invention;

[0025] Appendix Figure 3 This is a schematic diagram of the exploded structure of the resonant cavity of the present invention;

[0026] Appendix Figure 4 This is a schematic diagram of the exploded structure of the resonant cavity of the present invention;

[0027] Appendix Figure 5 This is a cross-sectional view of the resonant cavity of the present invention;

[0028] Appendix Figure 6 This is a cross-sectional view of the cigarette stick of the present invention located in the resonant cavity;

[0029] Appendix Figure 7This is an appendix to the present invention. Figure 6 Enlarged view of section A;

[0030] Appendix Figure 8 This is a cross-sectional view of the resonant cavity with impedance matching ring of the present invention;

[0031] Appendix Figure 9 This is a schematic diagram of the structure of the microwave conduit of the present invention;

[0032] The diagram shows the following labels: 1-Unit device; 2-Smoke channel, 210-Annular notch; 3-Smoke; 4-Detection unit; 5-Microwave generator module; 6-Detector module; 7-Resonant cavity, 710-Annular cover, 711-First waveguide ring, 712-Signal input terminal, 7121-First signal needle, 713-Signal output terminal, 7131-Second signal needle, 720-Flange, 721-Second waveguide ring, 722-Impedance matching ring, 730-Annular cavity, 740-Signal focusing slope; 8-Microwave conduit, 810-Third signal needle, 820-Fixing foot; 9-Processing module, 910-Fixing hole; 10-Hollow tube. Detailed Implementation

[0033] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0036] In the embodiments of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] See appendix Figure 1 To be continued Figure 9 The figure shows a specific embodiment of a microwave detection device module for a dual-channel cigarette production equipment provided by the present invention.

[0038] See appendix Figure 1 To be continued Figure 4 The microwave detection device module for dual-channel cigarette production equipment includes:

[0039] Two connected unit 1 devices are provided. Each unit 1 has a cigarette channel 2 that runs through it. Each unit 1 has a detection part 4 for detecting the density and humidity of the cigarette 3.

[0040] The detection unit 4 includes a microwave generating module 5 and a detector module 6 connected to the microwave generating module 5, as well as a resonant cavity 7 connected to the detector module 6 through a signal input terminal 712 and a signal output terminal 713. The cigarette channel 2 passes through the resonant cavity 7 and forms an annular notch 210 inside the resonant cavity 7. The resonant cavity 7 has a first waveguide ring 711 and a second waveguide ring 721 on both sides of the annular notch 210, which are annularly fitted to the outer wall of the cigarette channel 2. The distance between the first waveguide ring 711 and the second waveguide ring 721 is equal to the width of the annular notch 210. When the cigarette 3 is located in the cigarette channel 2, the microwave signal entering the resonant cavity 7 through the signal input terminal 712 will penetrate the cigarette 3 located in the annular notch 210 and be output to the detector module 6 through the signal output terminal 713.

[0041] The first waveguide ring 711 and the second waveguide ring 721 are surrounded by a signal focusing slope 740 at one end near the annular notch 210. The signal focusing slope 740 forms an angle greater than 90° and less than 180° with the cigarette channel 2, which is used to enhance the electric field strength of the microwave signal in the annular notch 210.

[0042] In the above embodiments, the device module adopts a modular design. A single device unit 1 can be used in a single-channel cigarette production equipment, and two device units 1 connected together can be used in a dual-channel cigarette production equipment. Through the modular design, the microwave detection device module of this embodiment can be compatible with both single-channel and dual-channel cigarette production equipment. In use, the cigarette 3 enters the resonant cavity 7 of the detection unit 4 through the cigarette channel 2. The microwave generating module 5 generates a microwave signal and transmits it to the detection module 6 connected to the microwave generating module 5. The detection module 6 transmits the microwave signal to the resonant cavity 7 through the signal input terminal 712. See Appendix Figure 5 The cigarette channel 2 forms an annular notch 210 inside the resonant cavity 7. The microwave signal entering the resonant cavity 7 through the signal input terminal 712 will penetrate the cigarette 3 located in the annular notch 210 and cause power attenuation. The signal is then output to the detector module 6 through the signal output terminal 713. Thus, the detector module 6 receives the microwave signal containing the density and humidity information of the cigarette 3, thereby enabling the detection unit 4 to complete the detection of the density and humidity of the cigarette 3. The detector module 6 can also perform signal conversion on the received microwave signal for subsequent calculation.

[0043] When the volume of the resonant cavity 7 is reduced, its resonant frequency increases, and the electric field strength generated by it decreases. This reduces the penetration depth of the electric field in the cigarette 3, making it less sensitive to the center density of the cigarette 3 during measurement, resulting in larger measurement errors and affecting the product quality of the cigarette 3. In this embodiment, the volume of the resonant cavity 7 is reduced to shorten the distance between the two cigarette channels 2, so that the microwave detection device module of this embodiment can be used in the dual-channel cigarette production equipment commonly used in the industry. To solve the problem of reduced electric field strength caused by the reduction in the volume of the resonant cavity 7, please refer to the appendix. Figure 3 and attached Figure 4 In this embodiment, a signal focusing slope 740 is provided around the end of the first waveguide ring 711 and the second waveguide ring 721 near the annular notch 210 of the resonant cavity 7. The signal focusing slope 740 is an annular slope, and the slope direction of the signal focusing slope 740 forms an angle greater than 90° and less than 180° with the cigarette channel 2. The signal focusing slope 740 of the first waveguide ring 711 and the signal focusing slope 740 of the second waveguide ring 721 are symmetrical to each other at the annular notch 210 of the cigarette channel 2, so that the width of the transition section formed between the first waveguide ring 711 and the second waveguide ring 721 gradually decreases from the annular cavity 730 toward the annular notch 210 until it is equal to the width of the annular notch 210. See Appendix Figure 7In this embodiment, the signal focusing slope 740 is the side surface of a truncated cone, and the angle formed between the signal focusing slope 740 and the cigarette channel 2 is 135°. The signal focusing slope 740 specifically changes the shape of the electric field distribution within the resonant cavity 7, causing the potential vertex to point towards the cigarette channel 2, effectively focusing the field lines and reducing the spread of microwaves along the length of the cigarette channel 2. The signal focusing slope 740 can project the field lines into the interior of the cigarette in the cigarette channel 2, making the electric field intensity inside the cigarette 3 located in the cigarette channel 2 stronger. This achieves the goal of ensuring detection accuracy while reducing the volume of the resonant cavity 7, allowing the two resonant cavities 7 to be arranged side by side in space. When two device units 1 equipped with resonant cavities 7 are joined together, the two resonant cavities 7 are side by side without needing to be staggered in the height direction, thereby reducing the height and overall volume of the device. At the same time, since the microwave detection device module in this embodiment is formed by joining two device units 1, when joined together, the microwave detection device module can be used in dual-channel cigarette production equipment, and when separated into device units 1, it can be used in single-channel cigarette production equipment, thus achieving compatibility with both single-channel and dual-channel cigarette production equipment.

[0044] See appendix Figure 1 and attached Figure 2 In the above embodiment, the cigarette channel 2 is located near the center of one edge of the device unit 1, and the axial distance between the cigarette channels 2 of the two connected device units 1 is 38mm. The axial distance between the two cigarette channels in common dual-channel cigarette production equipment is only 38mm. To be applicable to such dual-channel cigarette production equipment, the axial distance between the cigarette channels 2 of the two connected device units 1 in this embodiment is 38mm. The cigarette channel 2 is located near the center of one edge of the device unit 1, meaning the resonant cavity 7 is positioned near the center of one edge of the device unit 1. The other device unit 1 is rotated 180° and then joined with it to form the microwave detection device module for dual-channel cigarette production equipment in this embodiment. In this embodiment, the distance from the axis of the cigarette channel 2 of the device unit 1 to one edge of the device unit 1 is 19mm.

[0045] See appendix Figure 6 and attached Figure 7 As an optional embodiment, the cigarette channel 2 is further provided with a hollow tube 10 that fits against the inner wall of the cigarette channel 2. The cigarette 3 enters through the hollow tube 10 and passes through the resonant cavity 7. The hollow tube 10 separates the annular cavity 730 from the external environment, thereby preventing dust, tobacco, or other impurities generated during the production process from entering the resonant cavity 7. The hollow tube 10 is made of a non-conductive material. In this embodiment, the hollow tube 10 is made of plastic.

[0046] See appendix Figure 8In the above embodiment, the resonant cavity 7 includes an annular cover 710 and a flange 720 that cooperate to form an annular chamber 730. A first waveguide ring 711 is disposed on the annular cover 710, and a second waveguide ring 721 is disposed on the flange 720. Both the signal input terminal 712 and the signal output terminal 713 are disposed on the annular cover 710. An impedance matching ring 722 is also disposed on the flange 720. The impedance matching ring 722 is disposed between the second waveguide ring 721 and the sidewall of the annular chamber 730 and is coaxial with the second waveguide ring 721. The impedance matching ring 722 is used to make the impedance of the resonant cavity 7 close to 50 ohms. In this embodiment, the main purpose of the impedance matching ring 722 is to adjust the impedance matching between the resonant cavity 7 and the input circuit. Impedance matching is necessary for any microwave device or circuit, and the same is true for the resonant cavity 7. When considered as an energy storage structure, the resonant cavity 7 can only store the most microwave energy and reflect the least microwave power, achieving optimal coupling, by achieving impedance matching with the transmission line or waveguide. In this embodiment, the microwave generating module 5 and other devices are all standard devices designed with an impedance of 50 ohms. The impedance matching ring 722 can make the impedance of the resonant cavity 7 as close to 50 ohms as possible to achieve impedance matching, so as to minimize reflection loss. The resonant cavity 7 will have higher power output when receiving the same input power, which reduces signal attenuation, improves the signal-to-noise ratio, and thus improves detection accuracy.

[0047] In the above embodiment, the impedance matching ring 722 extends on the flange 720 toward the inner end face of the annular cover 710 and does not exceed the height of the second waveguide ring 721. In this embodiment, the length of the extension of the impedance matching ring 722 toward the inner end face of the annular cover 710, i.e., the height of the impedance matching ring 722, does not exceed the edge of the annular notch 210. The design of the resonant cavity 7 can be classified as a re-entrant coaxial cavity. The impedance matching ring 722 mainly adjusts the equivalent inductance of the resonant cavity 7 by adjusting the height of the impedance matching ring 722, thereby achieving the purpose of changing the impedance. In this embodiment, the optimal height of the impedance matching ring 722 is slightly higher than the height of the second waveguide ring 721, i.e., slightly higher than the edge of the annular notch 210. In this embodiment, for ease of machining, the height of the impedance matching ring 722 is equal to the height of the second waveguide ring 721, i.e., flush with the edge of the annular notch 210.

[0048] In the above embodiment, the diameter of the impedance matching ring 722 is the midpoint between the outer diameter of the second waveguide ring 721 and the inner diameter of the annular cavity 730, making the distance between the impedance matching ring 722 and the second waveguide ring 721 equal to the distance between the impedance matching ring 722 and the inner wall of the annular cavity 730. In this embodiment, the impedance matching ring 722 divides a portion of the resonant cavity 7 into two sub-cavities. When microwaves are reflected in the two sub-cavities, if the travel distances are inconsistent, the microwaves transmitted in the two sub-cavities are prone to mutual interference. In this embodiment, the diameter of the impedance matching ring 722 is the midpoint between the outer diameter of the second waveguide ring 721 and the inner diameter of the annular cavity 730, that is, the widths of the two sub-cavities are equal. When microwaves are reflected in the two sub-cavities, the travel distances are similar, making it easy for them to overlap and form resonance, significantly reducing the mutual interference of microwaves reflected in the two sub-cavities and reducing losses.

[0049] In the above embodiment, the signal input terminal 712 includes a first signal needle 7121, and the signal output terminal 713 includes a second signal needle 7131. Both the first signal needle 7121 and the second signal needle 7131 pass through the annular cover 710 and extend into the annular chamber 730, and are equidistantly arranged on both sides of the cigarette channel 2. The detector module 6 is provided with a circuit board. One end of the first signal needle 7121 and the second signal needle 7131 are connected to the circuit board of the detector module 6, and the other end passes through the annular cover 710 and extends into the annular chamber 730, and are equidistantly arranged on both sides of the cigarette channel 2. In this embodiment, the ends of the first signal needle 7121 and the second signal needle 7131 located in the annular chamber 730 are located on a plane perpendicular to the cigarette channel 2, where the middle part of the annular notch 210 is located. That is, the line connecting the first signal needle 7121 and the second signal needle 7131 passes through the middle part of the annular notch 210, and the annular notch 210 is close to the inner end face of the annular cover 710. In this embodiment, the first signal pin 7121 and the second signal pin 7131 are connected to the circuit board of the detector module 6 by soldering to reduce the interference received by the microwave during transmission.

[0050] See appendix Figure 9In the above embodiment, the microwave generating module 5 and the detector module 6 are connected by a microwave conduit 8. The microwave conduit 8 is equipped with a third signal pin 810, which is connected to both the microwave generating module 5 and the detector module 6, for transmitting signals emitted by the microwave generating module 5 to the detector module 6. In this embodiment, the microwave generating module 5 also has a circuit board. The third signal pin 810 in the microwave conduit 8 is connected to both the circuit boards of the microwave generating module 5 and the detector module 6. To avoid interference with the transmission of microwave signals, in this embodiment, the third signal pin 810 is connected to both the circuit boards of the microwave generating module 5 and the detector module 6 by soldering. A fixing pin 820 is also provided at the end of the microwave conduit 8 connected to the circuit board of the detector module 6. The fixing pin 820 is soldered to the circuit board of the detector module 6 to improve the stability of the microwave signal transmission in the microwave conduit 8.

[0051] In the above embodiment, the device unit 1 further includes a processing module 9 sleeved on the outside of the detection unit 4 and electrically connected thereto. The processing module 9 is used to control the detection unit 4 to perform corresponding test actions and to collect and process the signal data output by the detection unit 4. In the embodiment, the cigarette 3 enters the resonant cavity 7 of the detection unit 4 through the cigarette channel 2. The microwave generating module 5 generates a microwave signal and transmits it to the detector module 6 connected to the microwave generating module 5. The detector module 6 transmits the microwave signal to the resonant cavity 7 through the signal input terminal 712. The cigarette channel 2 forms an annular notch 210 inside the resonant cavity 7. The microwave signal entering the resonant cavity 7 through the signal input terminal 712 will penetrate the cigarette located in the annular notch 210. The power attenuation of cigarette 3 is output to the detector module 6 through the signal output terminal 713. The detector module 6 receives the microwave signal containing the density and humidity information of cigarette 3. The detector module 6 is connected to the processing module 9. The detector module 6 converts the received microwave signal into an analog signal and then transmits it to the processing module 9 for processing. The processing module 9 also includes a processor, an AD converter, and a microwave control circuit. The microwave control circuit is used to control the microwave generator module 5 to emit a sweep frequency signal. The AD converter is used to receive the analog signal transmitted from the detector module 6 and convert it into a digital signal to be sent to the processor for data processing. The processor calculates the density and humidity of cigarette 3 based on this.

[0052] In the above embodiment, the device unit 1 is generally rectangular, and the detection unit 4 is housed within the processing module 9. The microwave generating module 5, the detection module 6, and the processing module 9 are provided with mounting positions for accommodating the resonant cavity 7 or through holes for the cigarette channel 2 to pass through. The cigarette channel 2 avoids the geometric center of the device unit 1 and is located near the middle of the length direction of the device unit 1. Two device units 1 are rotated 180° and then joined together to form the microwave detection device module for a dual-channel cigarette production equipment in this embodiment. In this embodiment, the edge of the device unit 1 is provided with fixing holes 910. When two device units 1 are joined together, the two fixing holes 910 are close to each other, and some fasteners can be used to join and fix the two device units 1 together.

[0053] In summary, this embodiment provides a microwave detection device module for a dual-channel cigarette production equipment. It consists of two interconnected device units 1. A single device unit 1 can be used in a single-channel cigarette production equipment, while the two interconnected device units 1 can be used in a dual-channel cigarette production equipment. A first waveguide ring 711 and a second waveguide ring 721 are arranged on both sides of the annular notch 210 in the resonant cavity 7 of the device unit 1. A signal focusing ring is arranged around one end of the first waveguide ring 711 and the second waveguide ring 721 near the annular notch 210. The inclined surface 740 enhances the electric field strength of the microwave signal in the annular notch 210, allowing for a reduction in the volume of the resonant cavity 7 while maintaining detection accuracy. An impedance matching ring 722, coaxial with the second waveguide ring 721 and with a height not exceeding that of the second waveguide ring 721, is placed on the flange 720 of the resonant cavity 7, bringing the impedance of the resonant cavity 7 close to 50 ohms to minimize reflection loss. The diameter of the impedance matching ring 722 is set to the midpoint between the outer diameter of the second waveguide ring 721 and the inner diameter of the annular cavity 730. The resonant cavity 7 is divided into two equal-width sub-cavities by an impedance matching ring 722, making the reflection distances of microwaves in the two sub-cavities similar, thereby reducing mutual interference and loss during microwave reflection. A microwave guide tube 8 is provided to connect the microwave generating module 5 and the detector module 6, facilitating the transmission of signals from the microwave generating module 5 to the detector module 6. A processing module 9 is provided to control the detection unit 4 to perform corresponding test actions and to collect and process the signal data output by the detection unit 4. By setting the axial spacing of the cigarette channel 2 of the two spliced ​​device units 1 to 38mm, it is easy to apply to common dual-channel cigarette production equipment. This invention is used to detect cigarette density and humidity. It can reduce the volume of the resonant cavity while ensuring detection accuracy by increasing the field strength of the electric field generated by the resonant cavity and reducing losses. This allows the two device units to be spliced ​​side by side, compatible with single-channel and dual-channel cigarette production equipment, reducing the height and overall volume of the microwave detection device module, and lowering the development difficulty and maintenance cost of the device.

[0054] The embodiments described above are merely one of the preferred embodiments of the present invention. Ordinary variations and substitutions made by those skilled in the art within the scope of the technical solutions of the present invention should be included within the protection scope of the present invention.

Claims

1. A microwave detection device module for a dual-channel cigarette production equipment, characterized in that, include: Two device units (1) are connected side by side. The device unit (1) is provided with a cigarette channel (2) that runs through the device unit (1). The device unit (1) is provided with a detection part (4) for detecting the density and humidity of the cigarette (3). The detection unit (4) includes a microwave generating module (5) and a detector module (6) connected to the microwave generating module (5), and a resonant cavity (7) connected to the detector module (6) through a signal input terminal (712) and a signal output terminal (713). The cigarette channel (2) passes through the resonant cavity (7) and forms an annular notch (210) inside the resonant cavity (7). The resonant cavity (7) has annular fittings on both sides of the annular notch (210) that fit the outer wall of the cigarette channel (2). The first waveguide ring (711) and the second waveguide ring (721) are spaced apart by a distance equal to the width of the annular notch (210). When the cigarette (3) is located in the cigarette channel (2), the microwave signal entering the resonant cavity (7) through the signal input terminal (712) will penetrate the cigarette (3) located in the annular notch (210) and be output to the detector module (6) through the signal output terminal (713). The first waveguide ring (711) and the second waveguide ring (721) are provided with a signal focusing slope (740) around one end near the annular gap (210). The signal focusing slope (740) forms an angle greater than 90° and less than 180° with the cigarette channel (2). The signal focusing slope (740) of the first waveguide ring (711) and the signal focusing slope (740) of the second waveguide ring (721) are symmetrical to each other at the annular gap (210) of the cigarette channel (2), so that the width of the transition section formed between the first waveguide ring (711) and the second waveguide ring (721) gradually decreases from the annular cavity (730) toward the annular gap (210) until it is equal to the width of the annular gap (210), which is used to enhance the electric field strength of the microwave signal in the annular gap (210).

2. The microwave detection device module for a dual-channel cigarette production equipment according to claim 1, characterized in that, The resonant cavity (7) includes an annular cover (710) and a flange (720) that cooperate to form an annular cavity (730). The first waveguide ring (711) is disposed on the annular cover (710), and the second waveguide ring (721) is disposed on the flange (720).

3. A microwave detection device module for a dual-channel cigarette production equipment according to claim 2, characterized in that, The signal input terminal (712) and the signal output terminal (713) are both disposed on the annular cover (710). An impedance matching ring (722) is also disposed on the flange (720). The impedance matching ring (722) is disposed between the second waveguide ring (721) and the side wall of the annular cavity (730) and is coaxial with the second waveguide ring (721). The impedance matching ring (722) is used to make the impedance of the resonant cavity (7) close to 50 ohms.

4. A microwave detection device module for a dual-channel cigarette production equipment according to claim 3, characterized in that, The impedance matching ring (722) extends on the flange (720) toward the inner end face of the annular cover (710) and does not exceed the height of the second waveguide ring (721).

5. A microwave detection device module for a dual-channel cigarette production equipment according to claim 4, characterized in that, The diameter of the impedance matching ring (722) is the midpoint between the outer diameter of the second waveguide ring (721) and the inner diameter of the annular cavity (730), so that the distance between the impedance matching ring (722) and the second waveguide ring (721) is equal to the distance between the impedance matching ring (722) and the inner wall of the annular cavity (730).

6. A microwave detection device module for a dual-channel cigarette production equipment according to claim 3, characterized in that, The signal input terminal (712) includes a first signal needle (7121), and the signal output terminal (713) includes a second signal needle (7131). The first signal needle (7121) and the second signal needle (7131) both pass through the annular cover (710) and extend into the annular chamber (730) and are equidistantly arranged on both sides of the cigarette channel (2).

7. A microwave detection device module for a dual-channel cigarette production equipment according to claim 1, characterized in that, The angle between the signal gathering slope (740) and the cigarette channel (2) is 135°.

8. A microwave detection device module for a dual-channel cigarette production equipment according to claim 1, characterized in that, The microwave generating module (5) and the detector module (6) are connected by a microwave conduit (8). The microwave conduit (8) is provided with a third signal pin (810) that is connected to the microwave generating module (5) and the detector module (6) respectively, for transmitting the signal emitted by the microwave generating module (5) to the detector module (6).

9. A microwave detection device module for a dual-channel cigarette production equipment according to claim 1, characterized in that, The device unit (1) also includes a processing module (9) sleeved on the outside of the detection unit (4) and electrically connected thereto. The processing module (9) is used to control the detection unit (4) to perform corresponding test actions and to collect and process the signal data output by the detection unit (4).

10. A microwave detection device module for a dual-channel cigarette production equipment according to claim 1, characterized in that, The cigarette channel (2) is located near the center of one edge of the device unit (1), and the axial distance between the cigarette channels (2) of the two device units (1) connected side by side is 38 mm.

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