WO2020062934A1

WO2020062934A1 - Intelligent ultrasonic material level sensor

Info

Publication number: WO2020062934A1
Application number: PCT/CN2019/091043
Authority: WO
Inventors: 陈怡因
Original assignee: 伊玛精密电子（苏州）有限公司
Priority date: 2018-09-28
Filing date: 2019-06-13
Publication date: 2020-04-02
Also published as: DE202019106470U1

Abstract

An intelligent ultrasonic material level sensor, comprising an upper cover (11), a housing (1), a probe (31), and a circuit portion (2), wherein a fixed bracket (115) is provided in the housing (1), and the fixed bracket (115) is used to install the circuit portion (2); the circuit portion (2) is provided in the housing (1), and the circuit portion (2) comprises a power conversion module, an ultrasonic transducer unit (22), an ultrasonic driving circuit, an instrumentation amplifying circuit, a filtering and amplifying circuit, a gain adjusting module, a central processing unit and a temperature filtering circuit; the ultrasonic transducer unit (22) comprises a signal receiving and transmitting unit and a temperature detecting unit, and the ultrasonic transducer unit (22) is provided at an inner part of the probe (31). The present sensor is highly reliable and has precise detection accuracy, will not be affected by temperature, and has strong anti-interference capabilities; and sound speed learning may be achieved by means of a key learning mode.

Description

Intelligent ultrasonic material level sensor

Technical field

The invention relates to a material level detection instrument in the instrumentation industry, and particularly to an intelligent ultrasonic material level sensor.

Background technique

The ultrasonic level sensor is used in the level monitoring system. When the level reaches the set level threshold, a detection signal is generated to start the chain control system. The traditional ultrasonic level sensor has a complicated and bulky structure, difficult installation, and precision is easily affected by temperature. It has poor anti-interference ability and single function. It does not have the functions of fully automatic control, alarm, and activation of chain protection system for detection signals. Most of them are mainly potting, with complicated technology, inconvenient maintenance, poor corrosion resistance, large volume, and insufficient aesthetic appearance.

Summary of the Invention

In view of the shortcomings of the prior art described above, the object of the present invention is to provide an intelligent ultrasonic level sensor with high reliability, accurate detection accuracy, not affected by temperature, strong anti-interference ability, corrosion resistance, small size, and installation. Convenient corrosion-resistant all-metal ultrasonic level sensor.

In order to achieve the above object and other related objects, the present invention provides an intelligent ultrasonic level sensor, which includes an upper cover, a casing, a probe, and a circuit part. The casing is provided with a fixed bracket, and the fixed bracket is used for installing Said circuit portion; said circuit portion is disposed in said housing, said circuit portion includes a power conversion module, an ultrasonic transducer unit, an ultrasonic drive circuit, a meter amplifier circuit, a filter amplifier circuit, a gain adjustment module, a central processing unit, Temperature filtering circuit; the ultrasonic transducer unit includes a signal receiving and transmitting unit and a temperature detecting unit, and the ultrasonic transducer unit is disposed inside the probe.

Preferably, an output end of the temperature detection unit is connected to a temperature filter circuit, and an output signal of the temperature filter circuit is input to a central processing unit for processing; an ultrasonic drive circuit whose input end is connected to the central processing unit and whose output end is The ultrasonic transducer unit is connected for ultrasonic transmission; the output signal of the ultrasonic transducer unit is input to the instrument amplification circuit for first-stage signal amplification; the output end of the instrument amplification circuit is connected to the filter amplification circuit for secondary amplification; The output signal of the filter amplifier circuit is input to the central processing unit for analysis and processing; the input terminal of the gain adjustment module is connected to the central processing unit, and the output terminal is connected to the instrument amplifier circuit for first-stage amplification gain adjustment; as data processing The central processing unit of the controller is provided with a temperature compensation unit and a time distance calculation unit.

Preferably, the circuit part further includes an output unit and an output protection unit. The input end of the output unit is connected to the central processing circuit, and the switching value output of the monitoring distance signal is performed by an NPN transistor or a PNP transistor, and the current is 4-20 mA or voltage. 0 ～ 10V performs analog output of the monitoring distance signal; the input end of the output protection unit is connected to the output unit. Achieve short circuit protection, reverse polarity protection, overload protection, etc.

Preferably, the circuit part further includes a display driving unit and a display unit, an input end of which is connected to the central processing unit, and an output end of which is connected to the display unit for display signal output; and the ultrasonic transducer unit separately collects and measures the measured signals. The ambient temperature signal and the distance signal are transmitted to the central processing unit, and the processed data are output through the output unit and the display unit displays a numerical signal, respectively.

Preferably, the circuit part further includes a key control unit, and the key control unit and the display unit constitute a menu system through a central processing unit for user interaction. The menu system can simulate the output mode and switch point of the switch output. The output mode and height of the volume output and the learning and restoration of the ultrasonic sound speed and factory settings can be adjusted or corrected; at the same time, the current distance, temperature, or current and voltage can be displayed through the key control unit settings.

Preferably, the key control unit is composed of keys, and the keys are used for menu setting and function selection; the display unit is composed of three seven-segment digital tubes and six LED lights, and three seven-segment digital tubes are used for temperature display and target distance Value display and current or voltage value display, 6 LED lights are displayed as status lights, and the display unit is set in the display cover.

Preferably, the power conversion module is provided with an anti-interference, anti-static, and anti-lightning isolation component. The isolation component includes a magnetic bead and a choke coil. The choke coil is disposed at the input end of the power supply and is contained in the suppression circuit. At the same time, a magnetic bead is connected in parallel behind the choke coil to eliminate high-frequency interference signals in the circuit; at the same time, the power supply unit is connected to the casing and connected to the ground to release the inside of the circuit Excess charge and interference.

Preferably, the upper cover is provided with a display cover, a button, and a connector. The display cover includes a distance display unit, and the display cover is fixed from the inside of the upper cover by a pressing piece to display the current target distance, temperature, and current. Value or voltage value display and status display; keys are loaded from the surface of the housing to learn menu settings and function selections such as calibration target distance high and low points, switch point selection, etc .; a seal is provided on the connector, from the side of the upper cover The round hole extends into the shell, and the connector is used to connect external cables to supply power to the circuit part; plastic parts are used to fix the circuit part, which plays a role of anti-vibration, insulation and anti-interference.

Preferably, the probe includes a pressure ring, a seal ring, a transducer gasket, and an ultrasonic transducer unit. The transducer gasket wraps the ultrasonic transducer unit, and the transducer gasket can reduce the transducer's ultrasonic energy conversion. The pressure of the transducer unit, the sealing ring acts as a seal when the interference fit between the pressure ring, the ultrasonic transducer unit and the probe; a round hole is provided on the top of the pressure ring, and the round hole is used to strengthen the product Anti-interference ability ground wire.

Preferably, the probe is provided with a blind hole in the center of the cylinder, and a step is provided at each of the top, middle and bottom of the blind hole. The top step is provided with the fixed bracket, and the middle step is provided with the pressure ring. The ultrasonic transducer unit is placed on the bottom step, and the pressure ring is used to fix the ultrasonic transducer unit.

Preferably, the fixing bracket is disposed in the housing, and the fixing bracket is two symmetrical plastic pieces, the plastic pieces are semi-elliptical, and a bayonet is provided on the inner wall of the semi-ellipse for fixing The circuit board has the functions of anti-vibration, shielding and anti-interference.

Preferably, the housing and the probe are both made of acid and alkali resistant materials; the ultrasonic transducer unit is made of polyvinylidene fluoride, polytetrafluoroethylene, titanium alloy or stainless steel 316L. Has strong corrosion resistance.

Preferably, the overall height of the housing after being assembled with the probe is not higher than 82.5mm.

As mentioned above, the intelligent ultrasonic level sensor provided by the present invention has the following beneficial effects: high reliability, accurate detection accuracy, not affected by temperature, strong anti-interference ability, sound speed learning function, and can easily pass It can be realized by the key learning method, and it can reach IP68 protection level without potting. The structure and technology are simple, the cost is low, the maintenance is convenient, the corrosion resistance is small, the shape is beautiful, and the corrosion-resistant all-metal ultrasonic level sensor is easy to install.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a working principle diagram of an intelligent ultrasonic level sensor.

Figure 2 is a sectional view of an intelligent ultrasonic level sensor.

Figure 3 is a schematic diagram of the external structure of an intelligent ultrasonic level sensor.

Figure 4 is an exploded view of an intelligent ultrasonic level sensor.

1. housing, 11. upper cover, 111. pressing piece, 112. display cover, 113. key, 114. connector, 115. fixed bracket, 2. circuit part, 21. circuit board, 22. ultrasonic transducer Transducer unit, 3. probe part, 31. probe, 311. seal ring, 312. seal gasket, 313. pressure ring, 314. seal ring, 315. transducer gasket.

detailed description

The embodiments of the present invention will be described below with specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

See Figures 1 to 4. It should be noted that the structures, proportions, sizes, etc. shown in the drawings in this specification are only used to match the contents disclosed in the description for those familiar with this technology to understand and read, and are not intended to limit the implementation of the present invention. Limited conditions, so it does not have technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size shall still fall within the present invention without affecting the efficacy and the purpose that can be achieved by the present invention. The disclosed technical content must be within the scope. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this manual are only for the convenience of description and are not intended to limit the text. The scope of the invention that can be implemented, and the changes or adjustments in its relative relationship, should be regarded as the scope in which the invention can be implemented without substantial changes in the technical content.

As shown in FIG. 1 to FIG. 4, the present invention provides an intelligent ultrasonic level sensor, which includes an upper cover, a housing, a probe, and a circuit part. The housing is provided with a fixed bracket, and the fixed bracket is used for installing the Said circuit portion; said circuit portion is disposed in said housing, said circuit portion includes a power conversion module, an ultrasonic transducer unit, an ultrasonic drive circuit, a meter amplifier circuit, a filter amplifier circuit, a gain adjustment module, a central processing unit, Temperature filtering circuit; the ultrasonic transducer unit includes a signal receiving and transmitting unit and a temperature detecting unit, and the ultrasonic transducer unit is disposed inside the probe.

An output terminal of the temperature detection unit is connected to a temperature filter circuit, and an output signal of the temperature filter circuit is input to a central processing unit for processing; an ultrasonic drive circuit has an input terminal connected to the central processing unit, and an output terminal of the temperature drive circuit to an ultrasonic transducer. The transducer unit is connected for ultrasonic transmission; the output signal of the ultrasonic transducer unit is input to the instrumentation amplifier circuit for first-stage signal amplification; the output end of the instrumentation amplifier circuit is connected to the filter amplifier circuit for secondary amplification; the filter amplifier The output signal of the circuit is input to the central processing unit for analysis and processing; the input terminal of the gain adjustment module is connected to the central processing unit, and the output terminal is connected to the instrumentation amplifier circuit for first-stage amplification gain adjustment; as the center of the data processor A processing unit, which is provided with a temperature compensation unit and a time distance calculation unit.

Both the housing 1 and the probe 31 are made of acid and alkali resistant material; a fixing bracket 115 is provided in the housing 1, and the fixing bracket 115 is composed of two semi-ellipsoid plastic parts, and plastic can be used. It can also be other insulating materials, such as rubber products, other high-molecular polymers, etc., a bayonet is provided on the inner wall of the semi-ellipsoidal plastic part to fix the circuit part 2 to prevent vibration and shielding The anti-interference effect; the circuit part 2 includes a circuit board 21 and an ultrasonic transducer unit 22, a power conversion module, an ultrasonic drive circuit, an instrument amplifier circuit, a filter amplifier circuit, a gain adjustment module, a central processing unit, and a key control unit The temperature filter circuit, the display drive unit, the display unit, the output unit, and the output protection unit are all arranged on the circuit board 21; the ultrasonic transducer unit includes a signal receiving and transmitting unit and a temperature detecting unit, and the central processing unit can optionally use a single chip microcomputer, Or other data processing circuits composed of integrated circuits and peripheral components.

The ultrasonic transducer unit is made of a corrosion-resistant plastic material; the ultrasonic transducer unit 22 is arranged inside the probe 3, the housing 1 and the probe 3 are fixed by interference fit, and the circuit part 2 is provided inside the casing 1.

The key control unit is composed of key 113. Key 113 is used for menu setting and function selection. The display unit is composed of three seven-segment digital tubes and six LED lights. Three seven-segment digital tubes are used for temperature display, distance display of target objects, and The current current value or voltage value is displayed. Six LED lights are displayed as status lights. The display unit is set in the display cover 112.

The circuit part also includes an output unit and an output protection unit. The input end of the output unit is connected to the central processing circuit, and the switching value output of the monitoring distance signal is performed by an NPN transistor or a PNP transistor. The current is 4-20mA or the voltage is 0-10V. The analog output of the monitoring distance signal is performed; the input end of the output protection unit is connected to the output unit to achieve short circuit protection, reverse polarity protection, overload protection, etc.

The circuit part further includes a display driving unit and a display unit, an input end of which is connected to the central processing unit, and an output end of which is connected to the display unit for display signal output; the ultrasonic transducer unit collects the temperature of the measured environment, respectively The signal and the distance signal are transmitted to the central processing unit, and the processed data are output through the output unit and the display unit displays a numerical signal, respectively.

The circuit part further includes a key control unit. The key control unit and the display unit constitute a menu system for user interaction through a central processing unit. The menu system can control the output mode and switch point of the digital output, and the analog output. The output method, high and low points, and ultrasonic sound speed learning and factory settings can be adjusted or corrected; at the same time, the current distance, temperature, or current and voltage can be displayed through the key control unit settings.

The circuit works as follows:

The temperature detection unit is used to detect the temperature signal of the measured medium. After processing by the filter circuit, the detected temperature signal is transmitted to the central processing unit; the central processing unit outputs signals and inputs the ultrasonic drive circuit, and at the same time, the central processing unit starts timing and the ultrasonic drive The circuit is connected to the ultrasonic transducer for ultrasonic transmission; the ultrasonic transducer detects the ultrasonic signal returned after reaching the target, converts it into an electrical signal and outputs it to the instrumentation amplifier circuit for first-stage amplification; the instrumentation amplifier circuit is connected to the filter amplifier circuit for After the secondary filtering and amplification, the detected signal is transmitted to a single central processing unit; at the same time, the central processing unit stops timing and starts time and distance calculation and internal temperature drift compensation; the gain adjustment module, the output end is connected to the instrument amplification circuit, and the input end is connected The central processing unit adjusts the first-stage amplification gain within a precise time to achieve the automatic gain effect; at the same time, the central processing unit outputs serial output to the drive display unit, and the drive display unit outputs signals to the display unit. The code tube and LED lights display the temperature signal and the distance signal of the target; the key control unit can calibrate the ultrasonic sound velocity, and can also be used to select the output mode, output high and low points, switch points and other menu settings and function selection; The power conversion module is mainly used to provide the required voltage to each unit; the anti-interference module is used to prevent electromagnetic static electricity and other interference to improve the stability and reliability of the product. The anti-interference module is mainly composed of one or two anti-interference components, and then some techniques for enhancing anti-interference are adopted in the circuit layout. The anti-interference module, except for the aforementioned metal case, plastic parts, and ground wire, is mainly implemented by magnetic beads and common mode chokes on the circuit. In addition, some anti-interference is used on the PCB layout. Layout techniques, specifically, a common mode choke is provided at the input end of the power conversion module to suppress common mode interference signals in the circuit; at the same time, a magnetic bead is connected in parallel behind the choke to eliminate the circuit High-frequency interference signals; at the same time, the power conversion module is connected to the casing and connected to the ground to release excess charges and interference inside the circuit, thereby enhancing the anti-interference performance of the product.

The central processing unit generates a monitoring signal to the output unit. When the output type of the monitoring signal is a switch output, the switch output of the monitoring distance signal is performed through an NPN transistor or a PNP transistor; when the output type of the monitoring signal is analog During output, the analog distance output of the monitoring distance signal is performed by current 4-20mA or voltage 0-10V; according to the output mode, it is divided into two-wire system and three-wire system output.

The output unit has its input connected to the central processing unit and its output connected to the other input of the output protection unit. The output protection unit can implement various protection functions such as short circuit protection, reverse polarity protection, and overload protection through pure hardware.

In actual application, the housing 1 adopts a structure in which the upper cover 11 and the probe 31 are combined, which is convenient to manufacture and install. The overall height of the housing and the probe after assembly is not higher than 82.5mm, and the upper end of the probe 31 is Connected to the upper cover 11, the ultrasonic transducer unit is installed at the lower end of the probe 31, and the probe 31 plays a role of fixing and locking during installation.

As shown in FIG. 3, the upper cover 11 is provided with a display cover 112, a button 113, and a connector 114. A distance display unit is provided in the display cover 112. The display cover 112 is fixed to the inner surface of the upper cover from the inside of the cover through the pressing piece 111. , Used to display the current target distance, temperature, and current or voltage value display and status display; key 113 is loaded from the surface of the upper cover to learn menu settings such as calibration target distance high and low points, switch point selection, etc. And function selection; the connector 114 is provided with a sealing ring, which extends into the shell from the round hole on the side of the upper cover 11; the connector 114 is used to connect an external cable to supply power to the circuit part; a plastic piece 115 is used to fix the circuit part 2 , Play the role of anti-vibration, insulation, anti-interference.

The probe 31 is provided with two card slots, a seal ring 311 is provided on the upper card slot, and a seal pad 312 is provided on the lower card slot. The seal ring 311 and the seal pad 312 have the effect of waterproof and dustproof. The double-slot design greatly improves the sealing performance, plays a role of waterproof, moisture-proof and dust-proof, and also easily improves the explosion-proof level. The probe is provided with a blind hole in the center of the cylinder, and a step is provided at the top, middle and bottom of the blind hole. The top step is provided with the fixed bracket, the middle step is provided with the pressure ring, and the bottom The ultrasonic transducer unit is placed on a step, and the pressure ring is used to fix the ultrasonic transducer unit.

The probe 31 includes a pressure ring 313, a seal ring 314, a transducer gasket 315, and an ultrasonic transducer unit 316. The transducer gasket 315 wraps the ultrasonic transducer unit 316. The transducer gasket 315 can reduce the probe 31 For the squeeze of the ultrasonic transducer unit, the sealing ring 314 acts as a seal when the interference fit between the pressure ring 313, the ultrasonic transducer unit 316 and the probe 31; a round hole is provided on the top of the pressure ring 313, so A ground wire for enhancing the anti-interference ability of the product is installed in the circular hole, and the diameter of the circular hole is ≤1.5mm.

Both the upper cover 11 and the probe 31 are made of a corrosion-resistant material. The upper cover 11 and the probe 31 are fixed by an interference fit, and sealed by a sealing ring 311 and a gasket 312 on the probe 31.

As shown in Table 1, a menu is displayed for the present invention. The first column is the setting menu, the second column is the menu function note, the third column is the parameter setting range, the fourth column is the setting method, and the fifth column is a note describing the menu object.

For the setting method, refer to Table 1. There are two keys on the lower part of the display panel. The left MODE / ENTER key is the menu setting and confirmation function. Each time the menu is pressed, it is displayed on the digital tube. The right LEARN / SET key is the parameter setting. With the MODE / ENTER key, set the parameters of the corresponding menu (also shown on the digital tube), confirm the parameters and press the MODE / ENTER key again.

Table 1:

In the table above: "SP1" and "rP1" switch points: After setting SP1 and rP1, when SP1 is smaller than rP1, when the distance is shorter than SP1, the output is turned on, and when the distance is greater than rP1, the output is turned off ; When SP1 is larger than rP1, when the distance is shorter than rP1, the output is turned off; when the distance is longer than SP1, the output is turned on; when the distance is between SP1 and rP1, the output remains in the current state.

"ASP" and "AEP" switch points: After setting ASP and AEP, when the distance changes from ASP to AEP, the analog output changes from 20mA to 4mA or 10V to 0V.

"N-P" output 1 mode: In the menu "n-P" mode, you can set whether the output 1 mode is "PnP" or "nPn".

"U-i" output 2 mode: In the menu "U-i" mode, you can set output 2 mode, set to "v" for voltage output, and set to "i" for current output.

"DiS" digital tube display type: In the menu "DiS" mode, you can set the digital tube display type. Set to "d" to display the current detection distance value, set to "S" to display the currently set output 2 simulation Output value, set to "t" to display the current detected temperature value.

“Mor” advanced setting access password: This menu will only appear in the menu when the power is pressed after pressing the MODE / ENTER key. When the password is entered correctly, the menu will automatically join the various menus of the advanced settings. When the password is entered incorrectly, The menu is locked. When the menu is unlocked again, the menu will disappear.

“StU” sound speed learning setting: In “StU” mode, you can long press the LEARN / SET key to perform sound speed learning in the current environment.

"FAC" sound speed learning setting: In "FAC" mode, you can long press the LEARN / SET key to return the sound speed to the factory set value.

“IH” current high point setting: In “iH” mode, adjust the detection distance to the maximum current output, and then adjust the parameter to make the current parameter infinitely close to 20mA to reduce the output error.

"IL" current high point setting: In "iL" mode, adjust the detection distance to the current output at the minimum value, and then adjust the parameter to make the current parameter infinitely close to 4mA to reduce the output error.

“VH” current high point setting: In “vH” mode, adjust the detection distance to the maximum voltage output, and then adjust the parameter to make the current parameter infinitely close to 10V to reduce the output error.

In summary, the present invention provides an intelligent ultrasonic level sensor with high reliability, accurate detection accuracy, not affected by temperature, strong anti-interference ability, sound speed learning function, which can be realized by button learning; The seal fits with a non-glue sealing structure, and the protection level can reach IP68 protection. The shell is made of acid and alkali resistant materials, which is corrosion-resistant and durable. The structure is simple, the installation and maintenance are convenient, the volume is small, and the shape is beautiful. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

The above-mentioned embodiments merely illustrate the principle of the present invention and its effects, but are not intended to limit the present invention. Anyone familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field to which they belong without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

An intelligent ultrasonic level sensor is characterized in that it includes an upper cover, a housing, a probe, and a circuit part. The housing is provided with a fixed bracket, and the fixed bracket is used to install the circuit part; the circuit part It is arranged in the housing, and the circuit part includes a power conversion module, an ultrasonic transducer unit, an ultrasonic drive circuit, a meter amplifier circuit, a filter amplifier circuit, a gain adjustment module, a central processing unit, and a temperature filter circuit; The energy transducer unit includes a signal receiving and transmitting unit and a temperature detection unit, and the ultrasonic transducer unit is disposed inside the probe.
The intelligent ultrasonic level sensor according to claim 1, characterized in that: an output end of the temperature detection unit is connected with a temperature filter circuit, and an output signal of the temperature filter circuit is input to a central processing unit for processing; The driving circuit has an input end connected to the central processing unit, and an output end connected to the ultrasonic transducer unit for ultrasonic transmission; the output signal of the ultrasonic transducer unit is input to a meter amplifier circuit for first-stage signal amplification; The output terminal of the instrument amplifier circuit is connected to the filter amplifier circuit for secondary amplification; the output signal of the filter amplifier circuit is input to the central processing unit for analysis and processing; the gain adjustment module has an input terminal connected to the central processing unit and The output end is connected to the instrument amplification circuit for first-stage amplification gain adjustment. As a central processing unit of the data processor, the central processing unit is provided with a temperature compensation unit and a time distance calculation unit.
The intelligent ultrasonic level sensor according to claim 2, wherein the circuit part further comprises a display driving unit and a display unit, an input end of which is connected to the central processing unit, and an output end thereof is connected to the display unit. The connection is performed for display signal output; the ultrasonic transducer unit collects temperature signals and distance signals of the measured environment and transmits them to the central processing unit, and the processed data is output through the output unit and the display unit displays numerical signals.
The intelligent ultrasonic level sensor according to claim 1, wherein the circuit part further comprises a key control unit, and the key control unit and the display unit form a menu system through a central processing unit to perform user interaction. The menu system can adjust or correct the output mode and switch point of the digital output, the output mode and the high and low points of the analog output, and the learning and restoring of the ultrasonic sound speed. Distance, temperature or current, voltage.
The intelligent ultrasonic level sensor according to claim 4, characterized in that: the key control unit is composed of keys, and the keys are used for menu setting and function selection; the display unit is composed of three seven-segment digital tubes and six It is composed of LED lights, three seven-segment digital tubes for temperature display, target distance value display, and current or voltage value display. Six LED lights are used as status lights for display. The display unit is set in the display cover.
The intelligent ultrasonic level sensor according to claim 1, characterized in that: the power conversion module is provided with an isolation component for anti-interference, anti-static, and anti-lightning, and the isolation component includes magnetic beads and yoke. A choke coil is arranged at the input end of the power supply to suppress common mode interference signals in the circuit; a magnetic bead is connected in parallel behind the choke coil to eliminate high frequency interference signal power in the circuit The unit is connected to the housing and connected to the ground to release the extra charge and interference inside the circuit.
The intelligent ultrasonic level sensor according to claim 1, wherein the upper cover is provided with a display cover, buttons, and connectors, and a distance display unit is provided in the display cover, and the display cover passes through the upper cover. The pressing piece is fixed on the inner surface of the upper cover, which is used to display the current target distance, temperature, current current or voltage value display and status display; the keys are loaded from the surface of the upper cover to learn to calibrate the distance of the target. Menu setting and function selection such as point and switch point selection; The connector is provided with a sealing ring that extends into the shell from the round hole on the side of the upper cover. The connector is used to connect external cables and supply power to the circuit part; plastic parts are used to The fixed circuit part plays the role of anti-vibration, insulation and anti-interference.
The intelligent ultrasonic level sensor according to claim 1, wherein the probe comprises a pressure ring, a seal ring, an ultrasonic transducer unit, and a transducer gasket, and a seal is provided at the lower part of the pressure ring. Ring, the lower part of the sealing ring is provided with an ultrasonic transducer unit wrapped by a transducer gasket, and the probe is fixed by interference fit, and the transducer gasket can reduce the squeeze of the probe to the ultrasonic transducer unit, The sealing ring acts as a seal during interference fit between the pressure ring, the ultrasonic transducer unit and the probe; a round hole is provided on the top of the pressure ring, and a ground wire for enhancing the anti-interference ability of the product is installed in the round hole.
The intelligent ultrasonic level sensor according to claim 8, characterized in that: the probe is provided with a blind hole in the center of the cylinder, and a step is provided at each of the top, the middle and the bottom of the blind hole. The fixed bracket is placed on the steps, the pressure ring is placed on the middle step, and the ultrasonic transducer unit is placed on the bottom step, and the pressure ring is used to fix the ultrasonic transducer unit.
The intelligent ultrasonic level sensor according to claim 1, wherein the overall height of the casing and the probe after assembly is not higher than 82.5mm.