Device for detecting total number of bacterial colonies in milk

Abstract

The utility model discloses a device for detecting the total number of bacterial colonies in milk, which comprises a rack, and a PLC (programmable logic controller) and an audible and visual alarm are sequentially mounted on the outer side wall of the rack. When the milk sample collecting device runs, the self-locking motor in the shell is started to be matched with the transmission action of the screw rod and the nut seat to drive the nut seat to slide back and forth at the bottom of the shell, so that the driving frame and the sample collecting pipe can be driven to move back and forth, and the sample collecting pipe is controlled to collect a milk sample towards a production line pipeline; the sample collecting pipe can automatically move to the impedance analyzer main body to output a sample, the total number of bacterial colonies is indirectly quantified by measuring the electrical property change caused by microbial metabolism by utilizing an impedance method, and subsequently, the sample collecting pipe is driven to move to the clear water tank to suck clear water for washing, and is moved to the upper part of the sewage tank to empty the cleaned sewage; therefore, the device achieves a self-cleaning function, and the problem of cross contamination of different milk samples is avoided.

Description

Technical Field

[0001] This utility model relates to the field of microbial detection technology, specifically a device for detecting the total number of colonies in milk. Background Technology

[0002] Detecting the total bacterial count in milk is an important indicator for assessing its hygienic quality. In the actual production and processing of milk, testing devices are often used to detect and analyze the total bacterial count of milk on the production line. However, there are still some shortcomings in the actual use of devices for detecting the total bacterial count in milk.

[0003] Devices for detecting the total bacterial count in milk often require manual sample collection before sending them to the testing equipment. This manual sampling method is inefficient and makes it difficult to perform initial screening of samples or automated dilution pretreatment for samples with high bacterial counts. Directly sending all samples into the impedance analyzer for testing can affect the accuracy of the test results. Therefore, we propose a novel device for detecting the total bacterial count in milk. Utility Model Content

[0004] The purpose of this invention is to provide a device for detecting the total number of bacterial colonies in milk, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A device for detecting the total bacterial count in milk, comprising a frame, a PLC controller and an audible and visual alarm sequentially mounted on the outer wall of the frame, a housing welded to the top of the frame, a self-locking motor mounted on one side inside the housing, a lead screw connected to the output end of the self-locking motor, a nut seat screwed onto the lead screw, a connecting seat welded to the bottom of the nut seat, telescopic cylinders fixed on both sides of the connecting seat, a drive frame connected to the output end of the telescopic cylinders, a first cover and a second cover respectively fixed at both ends inside the drive frame, and the bottom of the first cover... The first cover is threaded with a sample collection tube, and the bottom of the second cover is threaded with a sterile buffer storage bottle. A microwave radar sensor is installed at the top of the first cover. A liquid pump is installed at the top of both the first and second covers. One end of the sample collection tube is provided with a waste liquid discharge tube connected to the liquid pump. A sampling tip is provided at the bottom of the sample collection tube. A sterile solenoid valve is installed on the sampling tip. An online conductivity sensor and a temperature sensor are installed sequentially on the sample collection tube above the sampling tip. A wastewater tank, impedance analyzer body, and clean water tank that match the sampling tip are installed sequentially at the bottom of the frame.

[0006] Preferably, the top of the sample collection tube is provided with a first threaded assembly tube that matches the first cap.

[0007] Preferably, the top of the sterile buffer storage bottle is provided with a second threaded assembly tube that matches the second cap.

[0008] Preferably, both the inner walls of the first cover and the second cover are provided with rubber sealing rings.

[0009] Preferably, the bottom of the sampling tip is threaded with a filter.

[0010] Preferably, the filter tip is provided with a milk fat filtration membrane layer inside, which facilitates the removal of milk fat from the milk sample during sampling and prevents clogging of the chip structure inside the impedance analyzer.

[0011] Preferably, the wastewater tank, the impedance analyzer body, and the clean water tank are all connected to the frame by a snap-fit ​​mechanism, which facilitates the independent disassembly and cleaning of the wastewater tank, the impedance analyzer body, and the clean water tank.

[0012] Preferably, the frame is made of stainless steel, and fixing screw holes are evenly provided at the bottom edge of the frame.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] (1) This device for detecting the total bacterial count in milk optimizes its performance by installing a liquid pump, etc. The liquid pump at the top of the first cover is activated, creating negative pressure inside the sample collection tube. Milk samples are collected through the sampling nozzle at the bottom of the sample collection tube, which extends into the production line pipeline. At the same time, the microwave radar sensor at the top of the first cover emits microwaves into the sample collection tube and analyzes the change in echo frequency to calculate the depth of the collected milk sample, so as to realize automated quantitative sampling. After quantitative sampling is completed, the online conductivity sensor and temperature sensor at the bottom of the sample collection tube automatically monitor the conductivity and temperature of the sample, and then send the monitored data to the PLC controller for calculation and processing. Excluding temperature interference, bacterial metabolic activity will change the milk The ion concentration of milk affects its conductivity. Therefore, based on the measured conductivity value compensated for by temperature data, milk can be initially screened to determine whether the sample is in a high bacterial count state. If the milk sample is not in a high bacterial count state, it can be directly transferred to the main body of the impedance analyzer for total colony count detection. Otherwise, it is necessary to open the pump on the second cover to draw sterile buffer from the sterile buffer storage bottle into the sample collection tube for sample dilution. Combined with the liquid depth measurement function of the microwave radar sensor, the PLC controller can mix the sterile buffer and sample in proportion before performing impedance testing. This can effectively avoid false negatives caused by excessively strong microbial metabolic activity leading to conductivity or fluorescence signals exceeding the instrument's range during impedance testing, thus improving detection accuracy.

[0015] (2) The device for detecting the total number of colonies in milk has optimized its structure by installing a lead screw, etc. On the one hand, the self-locking motor inside the housing is started, and with the transmission action of the lead screw and nut seat, the nut seat can be driven to slide back and forth at the bottom of the housing. This can drive the drive frame and sample collection tube to move back and forth. After the sample collection tube collects milk samples from the production line pipeline, it can automatically move to the main body of the impedance analyzer to output the sample. The total number of colonies is indirectly quantified by measuring the changes in electrical characteristics caused by microbial metabolism using the impedance method. Subsequently, the sample collection tube is moved to the clean water tank to draw clean water for rinsing, and then moved to the top of the wastewater tank to drain the wastewater after cleaning. This enables the device to achieve a self-cleaning function and avoid the problem of cross-contamination between different milk samples. On the other hand, the activation of two telescopic cylinders can drive the drive frame to rise and fall, which facilitates the automatic descent of the sample collection tube on the drive frame to the production line pipeline for automatic milk sample collection. Attached Figure Description

[0016] Figure 1 This is a front view structural diagram of the present invention;

[0017] Figure 2 This is a side view of the structure of this utility model;

[0018] Figure 3 This is a front view of the sample collection tube of this utility model in its disassembled state;

[0019] Figure 4 This is a front view structural diagram of the disassembled state of the sterile buffer storage bottle of this utility model;

[0020] Figure 5 This utility model Figure 1 Enlarged structural diagram at point A in the middle.

[0021] In the diagram: 1. Liquid pump; 2. Sample collection tube; 3. Wastewater tank; 4. Frame; 5. Telescopic cylinder; 6. Drive frame; 7. Housing; 8. Sterile buffer storage bottle; 9. PLC controller; 10. Audible and visual alarm; 11. Impedance analyzer body; 12. Clean water tank; 13. Self-locking motor; 14. Lead screw; 15. Connecting seat; 16. Online conductivity sensor; 17. Sterile solenoid valve; 18. First cover; 19. Filter tip; 20. Sampling pipette tip; 21. Temperature sensor; 22. First threaded assembly tube; 23. Second threaded assembly tube; 24. Waste liquid discharge tube; 25. Second cover; 26. Microwave radar sensor; 27. Nut seat. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0023] Please see Figure 1-5 The present invention provides an embodiment of a device for detecting the total number of colonies in milk, comprising a frame 4, wherein a PLC controller 9 and an audible and visual alarm 10 are sequentially mounted on the outer side wall of the frame 4;

[0024] A housing 7 is welded to the top of the frame 4. A self-locking motor 13 is installed on one side inside the housing 7. A lead screw 14 is connected to the output end of the self-locking motor 13. A nut seat 27 is screwed onto the lead screw 14. A connecting seat 15 is welded to the bottom of the nut seat 27.

[0025] Telescopic cylinders 5 are fixed on both sides of the connecting seat 15. The output end of the telescopic cylinder 5 is connected to the drive frame 6. The first cover 18 and the second cover 25 are fixed at both ends inside the drive frame 6 respectively.

[0026] The bottom of the first cover 18 is threaded with a sample collection tube 2, and the bottom of the second cover 25 is threaded with a sterile buffer storage bottle 8.

[0027] When in use, activating the two telescopic cylinders 5 can drive the drive frame 6 to move up and down, which facilitates the automatic descent of the sample collection tube 2 on the drive frame 6 into the production line pipeline for automatic milk sample collection.

[0028] A microwave radar sensor 26 is installed at the top of the inside of the first cover 18. A liquid pump 1 is installed at the top of both the first cover 18 and the second cover 25. A waste liquid discharge pipe 24 connected to the liquid pump 1 is provided at one end of the sample collection tube 2. A sampling pipette 20 is provided at the bottom of the sample collection tube 2. A sterile solenoid valve 17 is installed on the sampling pipette 20. An online conductivity sensor 16 and a temperature sensor 21 are installed in sequence on the sample collection tube 2 above the sampling pipette 20.

[0029] In use, the pump 1 at the top of the first cover 18 is activated, creating negative pressure inside the sample collection tube 2. Milk samples are collected through the sampling nozzle 20, which extends into the production line pipe at the bottom of the sample collection tube 2. Simultaneously, the microwave radar sensor 26 at the top of the first cover 18 emits microwaves into the sample collection tube 2 and analyzes the echo frequency changes to calculate the depth of the collected milk sample, enabling automated quantitative sampling. After quantitative sampling, the online conductivity sensor 16 and temperature sensor 21 at the bottom of the sample collection tube 2 automatically monitor the sample's conductivity and temperature, sending the monitored data to the PLC controller 9 for processing. This excludes temperature interference, as bacterial metabolic activity alters the ion concentration of the milk, thus affecting its conductivity. Therefore, based on the measured conductivity value compensated by temperature data, milk can be initially screened to determine whether the sample is in a high bacterial count state. If the milk sample is not in a high bacterial count state, it can be directly transferred to the main body 11 of the impedance analyzer for total colony count detection. Otherwise, the pump 1 on the second cover 25 needs to be opened to extract the sterile buffer solution inside the sterile buffer storage bottle 8 into the sample collection tube 2 for sample dilution. With the liquid depth measurement function of the microwave radar sensor 26, the PLC controller 9 can mix the sterile buffer solution and the sample in proportion before performing impedance testing. This can effectively avoid false negatives caused by excessive microbial metabolic activity leading to conductivity or fluorescence signals exceeding the instrument's range during impedance testing, thus improving detection accuracy.

[0030] Inside the bottom of the frame 4, a wastewater tank 3, an impedance analyzer body 11, and a clean water tank 12, which are matched with the sampling pipette head 20, are installed in sequence.

[0031] In use, the self-locking motor 13 inside the housing 7 starts, and with the transmission action of the lead screw 14 and the nut seat 27, it can drive the nut seat 27 to slide back and forth at the bottom of the housing 7. This can drive the drive frame 6 and the sample collection tube 2 to move back and forth. After the sample collection tube 2 collects milk samples from the production line pipeline, it can automatically move to the impedance analyzer body 11 to output the sample. The impedance method is used to indirectly quantify the total number of colonies by measuring the changes in electrical characteristics caused by microbial metabolism. Subsequently, the sample collection tube 2 is moved to the clean water tank 12 to draw clean water for rinsing, and then moved to the top of the wastewater tank 3 to drain the wastewater after cleaning. This enables the device to achieve a self-cleaning function and avoids the problem of cross-contamination between different milk samples.

[0032] The top of the sample collection tube 2 is provided with a first threaded assembly tube 22 that matches the first cover 18;

[0033] The top of the sterile buffer storage bottle 8 is provided with a second threaded assembly tube 23 that matches the second cap 25;

[0034] Rubber sealing rings are provided on the inner sidewalls of the first cover 18 and the second cover 25;

[0035] The bottom of the sampling tip 20 is threaded with a filter tip 19;

[0036] The filter tip 19 is equipped with a milk fat filtration membrane layer inside, which makes it easy to remove milk fat from the milk sample during sampling and prevents clogging of the chip structure inside the impedance analyzer body 11.

[0037] The wastewater tank 3, the impedance analyzer body 11, and the clean water tank 12 are all connected to the frame 4 by a snap-fit ​​connection, which makes it easy to disassemble and clean the wastewater tank 3, the impedance analyzer body 11, and the clean water tank 12 independently.

[0038] The frame 4 is made of stainless steel, and there are evenly spaced fixing screw holes along the bottom edge of the frame 4.

[0039] In this embodiment, during use: the self-locking motor 13 inside the housing 7 starts, and in conjunction with the transmission action of the lead screw 14 and the nut seat 27, it drives the nut seat 27 to slide back and forth at the bottom of the housing 7. This drives the drive frame 6 and the sample collection tube 2 to move back and forth. After the sample collection tube 2 collects milk samples from the production line pipeline, it can automatically move to the impedance analyzer body 11 to output the sample. The impedance method is used to indirectly quantify the total number of colonies by measuring the changes in electrical characteristics caused by microbial metabolism. Subsequently, the sample collection tube 2 is moved to the clean water tank 12 to draw clean water for rinsing, and then moved above the wastewater tank 3 to drain the wastewater after cleaning. This enables the device to achieve a self-cleaning function. This avoids cross-contamination between different milk samples. Furthermore, activating the two telescopic cylinders 5 allows the drive frame 6 to move up and down, facilitating the automatic descent of the sample collection tube 2 onto the production line pipe for automatic milk sample collection. During operation, the pump 1 at the top of the first cover 18 activates, creating negative pressure inside the sample collection tube 2. The sampling nozzle 20, extending from the bottom of the sample collection tube 2 into the production line pipe, collects the milk sample. Simultaneously, the microwave radar sensor 26 at the top of the first cover 18 emits microwaves into the sample collection tube 2 and analyzes the echo frequency changes to calculate the depth of the collected milk sample, thus achieving automated quantitative sampling. After quantitative sampling is completed, the online conductivity sensor 16 and temperature sensor 21 at the bottom of the sample collection tube 2 will automatically monitor the conductivity and temperature of the sample, and then send the monitored data to the PLC controller 9 for calculation and processing. Temperature interference and bacterial metabolic activity can alter the ion concentration of milk, thus affecting conductivity. Therefore, based on the measured conductivity value compensated for by temperature data, the milk can be initially screened to determine whether the sample is in a high bacterial count state. If the milk sample is not in a high bacterial count state, it can be directly sent to the impedance analyzer body 11 for total colony count detection. Otherwise, the pump 1 on the second cover 25 needs to be opened to extract the contents of the sterile buffer storage bottle 8. The sterile buffer solution is added to the sample collection tube 2 to dilute the sample. Combined with the liquid depth measurement function of the microwave radar sensor 26, the PLC controller 9 can mix the sterile buffer solution and sample in proportion before performing impedance testing. This can effectively avoid false negatives caused by excessive microbial metabolic activity leading to conductivity or fluorescence signals exceeding the instrument's range during impedance testing, thus improving detection accuracy. In addition, a filter 19 is threaded to the bottom of the sampling tip 20, and a milk fat filter membrane is set inside the filter 19. This facilitates the removal of milk fat from the milk sample during sampling, preventing blockage of the chip structure inside the impedance analyzer body 11 and extending the instrument's service life.

Claims

1. A device for detecting the total bacterial count in milk, characterized in that, The system includes a frame (4), on which a PLC controller (9) and an audible and visual alarm (10) are sequentially installed. A housing (7) is welded to the top of the frame (4). A self-locking motor (13) is installed on one side inside the housing (7). A lead screw (14) is connected to the output end of the self-locking motor (13). A nut seat (27) is screwed onto the lead screw (14). A connecting seat (15) is welded to the bottom of the nut seat (27). Telescopic cylinders (5) are fixed on both sides of the connecting seat (15). A drive frame (6) is connected to the output end of the telescopic cylinder (5). A first cover (18) and a second cover (25) are fixed to the two ends inside the drive frame (6). A sample collection tube (2) is threaded to the bottom of the first cover (18). The second cover (25) is threaded to the bottom of the second cover (25). 5) has a sterile buffer storage bottle (8) connected to the bottom thread. A microwave radar sensor (26) is installed at the top inside the first cover (18). A liquid pump (1) is installed at the top of both the first cover (18) and the second cover (25). A waste liquid discharge pipe (24) connected to the liquid pump (1) is provided at one end of the sample collection tube (2). A sampling pipette (20) is provided at the bottom of the sample collection tube (2). A sterile solenoid valve (17) is installed on the sampling pipette (20). An online conductivity sensor (16) and a temperature sensor (21) are installed in sequence on the sample collection tube (2) above the sampling pipette (20). A wastewater tank (3), an impedance analyzer body (11), and a clean water tank (12) that match the sampling pipette (20) are installed in sequence at the bottom inside the frame (4).

2. The device for detecting the total bacterial count in milk according to claim 1, characterized in that: The top of the sample collection tube (2) is provided with a first threaded assembly tube (22) that matches the first cover (18).

3. The device for detecting the total bacterial count in milk according to claim 1, characterized in that: The top of the sterile buffer storage bottle (8) is provided with a second threaded assembly tube (23) that matches the second cap (25).

4. The device for detecting the total bacterial count in milk according to claim 1, characterized in that: Both the inner walls of the first cover (18) and the second cover (25) are provided with rubber sealing rings.

5. The device for detecting the total bacterial count in milk according to claim 1, characterized in that: The bottom of the sampling tip (20) is threaded with a filter (19).

6. The device for detecting the total bacterial count in milk according to claim 5, characterized in that: The filter tip (19) is provided with a milk fat filtration membrane layer inside.

7. The device for detecting the total bacterial count in milk according to claim 1, characterized in that: The wastewater tank (3), the impedance analyzer body (11), and the clean water tank (12) are all connected to the frame (4) by a snap-fit ​​connection.

8. The device for detecting the total bacterial count in milk according to claim 1, characterized in that: The frame (4) is made of stainless steel, and fixing screw holes are evenly provided at the bottom edge of the frame (4).

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