CN211626516U - Sensor probe - Google Patents

Abstract

The utility model provides a sensor probe, including sensor housing, a circuit board, the gland, press the cap, the clamping ring with be located the intra-annular seal cover of clamping ring, the circuit board is installed in sensor housing's inner chamber, the gland, press the cap, the clamping ring, the center of seal cover all is equipped with the through-hole that is used for the cable to pass, the surface of the first end of gland is connected with the inner wall cooperation at sensor housing's top, when the cable passes the circuit board of through-hole and sensor housing's inner chamber and is connected, inner wall and the outer wall cooperation of pressing the cap through the second end of gland, can the axial compress tightly the clamping ring, and then can the axial compress tightly the seal cover through the clamping ring. Therefore, compared with the prior art, the utility model provides a sensor probe can press from both sides tight sensor cable and make it reach waterproof dirt-proof effect, can make the structure of sensor easily miniaturized simultaneously.

Description

Sensor probe

Technical Field

The utility model relates to a monitoring facilities technical field, in particular to sensor probe.

Background

In sensors widely used in the fields of machinery, ships, rail transit, etc., an internal circuit board contains a sensing device for sensing a physical quantity of a measured position, wherein the circuit board generally performs signal transmission with the outside through a connecting wire or a cable. In order to fix and protect the wires or cables, a cable locking structure is generally required to be additionally arranged at the tail of the sensor, so that the waterproof and dustproof effects are achieved.

In the prior art, the cable of the sensor is generally fixed by using a cable fixing head which is purchased from the market. Therefore, when designing the structure of the sensor, it is necessary to consider integrating the attachment method of the cable fixing head, which increases the design outer dimension of the sensor, and is not favorable for the miniaturization of the sensor structure.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides a sensor probe can press from both sides tight sensor cable and make its waterproof dustproof, can make the structure of sensor easily miniaturized simultaneously.

The utility model provides a sensor probe, include sensor housing, circuit board, gland, pressure cap, clamping ring and be located intra-annular seal cover of pressure, the circuit board install in sensor housing's inner chamber, the surface of the first end of gland with the inner wall cooperation at sensor housing's top is connected, the inner wall of the second end of gland with the outer wall cooperation of pressure cap compresses tightly with the axial the clamping ring, the clamping ring and then the axial compresses tightly the seal cover, the center of gland, pressure cap, clamping ring, seal cover all is equipped with the through-hole that is used for the cable to pass.

Preferably, the periphery of the bottom of the sensor housing is provided with a first outer conical surface for signal transmission, the inner wall of the bottom of the sensor housing is further provided with a first inner conical surface, and the periphery of the first end of the circuit board is provided with a second outer conical surface matched with the first inner conical surface.

Preferably, a step plate for welding the pin of the temperature measuring element is arranged at the first end of the circuit board, the thickness of the step plate is smaller than that of the circuit board, and the first end of the gland abuts against the second end of the circuit board. Preferably, the inner wall in the middle part of the sensor housing is provided with a guide groove, and the periphery of the second end of the circuit board is provided with a protrusion matched with the guide groove.

Preferably, the first end of gland is equipped with the bayonet socket, the second end of circuit board be equipped with bayonet socket complex spacing step. Preferably, the circuit board includes a horizontal plate mounted to the bottom of the sensor housing and a vertical plate fixed to the horizontal plate.

Preferably, the inner cavity of the sensor shell is provided with a sleeve, a first end of the sleeve abuts against the horizontal plate, and a second end of the sleeve abuts against the gland.

Preferably, the inner wall of the bottom of the sensor housing is provided with a second inner conical surface, the horizontal plate comprises a first horizontal circular plate and a second horizontal circular plate which are matched with the second inner conical surface, the first end of the sleeve abuts against the first horizontal circular plate, and the diameter of the first horizontal circular plate is larger than that of the second horizontal circular plate.

Preferably, a sensitive element and a signal conditioning circuit are mounted on the circuit board, the sensitive element is used for sensing the vibration impact physical quantity of the measured position and converting the vibration impact physical quantity into a charge signal, and the signal conditioning circuit is used for converting the charge signal output by the sensitive element into a voltage signal.

Preferably, the signal conditioning circuit comprises a first charge amplification module, a second charge amplification module and a differential amplification module;

the input end of the first charge amplification module and the input end of the second charge amplification module are respectively connected with two ends of the sensitive element and are used for converting the charge signal output by the sensitive element into a voltage signal;

the first input end and the second input end of the differential amplifying module are respectively connected with the output end of the first charge amplifying module and the output end of the second charge amplifying module, and the output end of the differential amplifying module is connected with the input end of a rear-stage detection system and used for differentially amplifying voltage signals output by the first charge amplifying module and the second charge amplifying module.

Preferably, the first charge amplification module comprises a first operational amplifier, a first capacitor, a first resistor and a second resistor, and the second charge amplification module comprises a second operational amplifier, a second capacitor, a third resistor and a fourth resistor;

the inverting input end of the first operational amplifier is used as the input end of the first charge amplification module, the non-inverting input end of the first operational amplifier is connected with a reference voltage, the output end of the first operational amplifier is used as the output end of the first charge amplification module, two ends of the first capacitor are respectively connected with the inverting input end of the first operational amplifier and the output end of the first operational amplifier, the first end of the first resistor is connected with the inverting input end of the first operational amplifier, the second end of the first resistor is connected with the first end of the second resistor, and the second end of the second resistor is connected with the output end of the first operational amplifier;

the inverting input end of the second operational amplifier is used as the input end of the second charge amplification module, the non-inverting input end of the second operational amplifier is connected to the reference voltage, the output end of the second operational amplifier is used as the output end of the second charge amplification module, two ends of the second capacitor are respectively connected with the inverting input end of the second operational amplifier and the output end of the second operational amplifier, the first end of the third resistor is connected with the inverting input end of the second operational amplifier, the second end of the third resistor is connected with the first end of the fourth resistor, and the second end of the fourth resistor is connected with the output end of the second operational amplifier;

the differential amplification module comprises a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor and a third operational amplifier;

a first end of the fifth resistor is used as a first input end of the differential amplification module, a second end of the fifth resistor is respectively connected with a first end of the sixth resistor and an inverting input end of the third operational amplifier, a second end of the sixth resistor is connected to the reference voltage, a first end of the seventh resistor is used as a second input end of the differential amplification module, a second end of the seventh resistor is respectively connected with a first end of the eighth resistor and a non-inverting input end of the third operational amplifier, a second end of the eighth resistor is connected with an output end of the third operational amplifier, and a common end of the eighth resistor is used as an output end of the differential amplification module.

Preferably, the signal conditioning circuit further includes a bootstrap module, configured to boost a voltage of the voltage signal output by the first charge amplification module and the second charge amplification module.

Preferably, the bootstrap module comprises a ninth resistor, a tenth resistor and a third capacitor;

the first end of the ninth resistor is connected with the connection node of the second end of the first resistor and the first end of the second resistor, the second end of the ninth resistor is connected with the first end of the third capacitor, the second end of the third capacitor is connected with the first end of the tenth resistor, and the second end of the tenth resistor is connected with the connection node of the second end of the third resistor and the first end of the fourth resistor.

Preferably, the bootstrap module comprises an eleventh resistor and a fourth capacitor;

the first end of the eleventh resistor is connected with a connection node between the second end of the first resistor and the first end of the second resistor, the second end of the eleventh resistor is connected with the first end of the fourth capacitor, and the second end of the fourth capacitor is connected with a connection node between the second end of the third resistor and the first end of the fourth resistor.

Preferably, the signal conditioning circuit further comprises an anti-interference module for enhancing the anti-interference capability of the sensitive element.

Preferably, the anti-interference module comprises a twelfth resistor, a thirteenth resistor, a fifth capacitor and a sixth capacitor;

a first end of the twelfth resistor is connected to the first end of the sensing element and the first end of the fifth capacitor, a second end of the twelfth resistor is connected to the first end of the thirteenth resistor, a second end of the thirteenth resistor is connected to the second end of the sensing element and the first end of the sixth capacitor, a common terminal of the twelfth resistor and the thirteenth resistor is connected to the reference voltage, a second end of the fifth capacitor is connected to the input terminal of the first charge amplification module, and a second end of the sixth capacitor is connected to the input terminal of the second charge amplification module.

Preferably, the interference rejection module comprises a fourteenth resistor, a seventh capacitor and an eighth capacitor;

a first end of the fourteenth resistor is connected to the first end of the sensing element and the first end of the seventh capacitor, a second end of the fourteenth resistor is connected to the second end of the sensing element and the first end of the eighth capacitor, a second end of the seventh capacitor is connected to the input end of the first charge amplification module, and a second end of the eighth capacitor is connected to the input end of the second charge amplification module.

Preferably, the signal conditioning circuit further comprises a first power supply processing module;

the input end of the first power supply processing module is connected with an input power supply, the first output end of the first power supply processing module is used for providing power supply voltage, and the second output end of the first power supply processing module is used for providing the reference voltage.

Preferably, the first power supply processing module comprises a diode, a fifteenth resistor, a ninth capacitor, a tenth capacitor and a first voltage regulator tube;

the anode of the diode is used as the input end of the first power processing module, the cathode of the diode is respectively connected with the first end of the fifteenth resistor and the first end of the ninth capacitor, the common end of the diode is used as the first output end of the first power processing module, the second end of the fifteenth resistor is respectively connected with the first end of the tenth capacitor and the cathode of the first voltage regulator tube, the common end of the fifteenth resistor is used as the second output end of the first power processing module, and the second end of the ninth capacitor, the second end of the tenth capacitor and the anode of the first voltage regulator tube are all connected with the ground.

Preferably, the signal conditioning circuit further comprises a second power supply processing module;

the input end of the second power supply processing module is connected with the second output end of the first power supply processing module, and the output end of the second power supply processing module is used for supplying power to the temperature measuring element.

Preferably, the second power supply processing module comprises a sixteenth resistor, an eleventh capacitor and a second voltage regulator tube;

and a first end of the sixteenth resistor is used as an input end of the second power supply processing module, a second end of the sixteenth resistor is respectively connected with a first end of the eleventh capacitor and a cathode of the second voltage-stabilizing tube, a common end of the sixteenth resistor is used as an output end of the second power supply processing module, and a second end of the eleventh capacitor and an anode of the second voltage-stabilizing tube are both connected with the ground.

Preferably, the second power supply processing module comprises a fourth operational amplifier, a seventeenth resistor and a twelfth capacitor;

the non-inverting input end of the fourth operational amplifier is used as the input end of the second power supply processing module, the inverting input end of the fourth operational amplifier is respectively connected with the output end of the fourth operational amplifier and the first end of the seventeenth resistor, the second end of the seventeenth resistor is connected with the first end of the twelfth capacitor, the common end of the seventeenth resistor is used as the output end of the second power supply processing module, and the second end of the twelfth capacitor is connected with the ground.

Preferably, the signal conditioning circuit further comprises an electrostatic protection module for providing electrostatic protection;

the electrostatic protection module comprises a first electrostatic discharge tube, a second electrostatic discharge tube, a third electrostatic discharge tube and a fourth electrostatic discharge tube;

the first end of the first electrostatic discharge tube is connected with the input end of the first power supply processing module, the first end of the second electrostatic discharge tube is connected with the second output end of the first power supply processing module, the first end of the third electrostatic discharge tube is connected with the output end of the differential amplification module, the first end of the fourth electrostatic discharge tube is connected with the output end of the temperature measuring element, and the second end of the first electrostatic discharge tube, the second end of the second electrostatic discharge tube, the second end of the third electrostatic discharge tube and the second end of the fourth electrostatic discharge tube are all connected with the ground.

The utility model provides a sensor probe, including sensor housing, a circuit board, the gland, press the cap, the clamping ring with be located the intra-annular seal cover of clamping ring, the circuit board is installed in sensor housing's inner chamber, the gland, press the cap, the clamping ring, the center of seal cover all is equipped with the through-hole that is used for the cable to pass, the surface of the first end of gland is connected with the inner wall cooperation at sensor housing's top, when the cable passes the circuit board of through-hole and sensor housing's inner chamber and is connected, inner wall and the outer wall cooperation of pressing the cap through the second end of gland, can the axial compress tightly the clamping ring, and then can the axial compress tightly the seal cover through the clamping ring. Therefore, compared with the prior art, the utility model provides a sensor probe can press from both sides tight sensor cable and make it reach waterproof dirt-proof effect, can make the structure of sensor easily miniaturized simultaneously.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a sensor probe according to an embodiment of the present invention;

fig. 2 is a schematic perspective view of a sensor housing according to an embodiment of the present invention;

fig. 3 is a schematic cross-sectional view of a sensor housing according to an embodiment of the present invention;

fig. 4 is a schematic perspective view of a circuit board according to an embodiment of the present invention;

fig. 5 is a schematic front view of a circuit board according to an embodiment of the present invention;

fig. 6 is a schematic left view of a circuit board according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of another sensor probe according to an embodiment of the present invention;

fig. 8 is a schematic perspective view of another circuit board according to an embodiment of the present invention;

fig. 9 is a schematic front view of another circuit board according to an embodiment of the present invention;

fig. 10 is a left side schematic view of another circuit board according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a signal conditioning circuit according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of another signal conditioning circuit according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of another signal conditioning circuit according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of a first power processing module according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of a second power processing module according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of another second power processing module according to an embodiment of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or be indirectly disposed on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, as used herein, refer to an orientation or positional relationship indicated in the drawings that is solely for the purpose of facilitating the description and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating 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 the present application, the meaning of a plurality of or a plurality of is two or more unless specifically limited otherwise.

It should be understood that the structures, ratios, sizes, and the like shown in the drawings and described in the specification are only used for understanding and reading the contents disclosed in the specification, and are not used for limiting the conditions that the present application can implement, so the present invention has no technical significance, and any structural modification, ratio relationship change or size adjustment should still fall within the scope of the technical content disclosed in the present application without affecting the efficacy and the achievable purpose of the present application.

Please refer to fig. 1 to 6, the embodiment of the utility model provides a sensor probe, including sensor housing 1, circuit board 2, gland 3, press cap 4, clamping ring 5 and the seal cover 6 that is located clamping ring 5, circuit board 2 installs in sensor housing 1's inner chamber, the surface of the first end of gland 3 is connected with the inner wall cooperation at sensor housing 1's top, the inner wall of the second end of gland 3 and the outer wall cooperation of pressing cap 4 compress tightly clamping ring 5 with the axial, clamping ring 5 and then axial compress tightly seal cover 6, gland 3, press cap 4, the center of clamping ring 5 and seal cover 6 all is equipped with the through-hole that is used for cable 7 to pass.

When the sensor probe is installed, one end of the sensor shell extends into the installation hole of the measured part to ensure that the physical quantity of the measured position is accurately sensed, and the other end of the sensor shell is connected with the acquisition instrument through the connecting cable to transmit the sensed physical quantity to the acquisition instrument. The utility model discloses in, sensor housing 1's bottom indicates its one end of deepening in the surveyed part mounting hole, and sensor housing 1's top indicates its one end of being connected through connecting cable and collection instrument.

The embodiment of the utility model provides an in, circuit board 2 is installed to sensor housing 1's inner chamber, can be sensitive by the physical quantity of position of being surveyed through the sensing element on the circuit board 2, and gland 3, pressure cap 4, clamping ring 5 and seal cover 6's center all is equipped with the through-hole that is used for cable 7 to pass, and cable 7 can pass through-hole connecting circuit board 2 and carry out signal transmission. Through the outer surface of the first end of the gland 3 and the inner wall of the top of the sensor housing 1 in a matching connection, axial pressure can be applied to the circuit board 2, so that the circuit board 2 is fixed. Be equipped with seal cover 6 in the clamping ring 5, the inner wall through the second end of gland 3 and the outer wall cooperation of pressing cap 4 can the axial compress tightly clamping ring 5, and then can compress tightly seal cover 6 through clamping ring 5 to it makes it reach waterproof dirt-proof effect to press from both sides tight cable 7, from this, need not to consider when sensor probe carries out structural design externally connecting hose cable fixed head, can make the structure of sensor easily miniaturize. Therefore, compared with the prior art, the sensor cable can be clamped to achieve the waterproof and dustproof effects, and the structure of the sensor can be easily miniaturized.

During specific implementation, the outer surface of the first end of the gland 3 and the inner wall of the top of the sensor shell 1 can adopt interference fit, and meanwhile, the joint can be welded by using a laser welding process, so that the installation reliability is ensured. The inner wall of the second end of the gland 3 and the outer wall of the gland 4 can adopt threaded connection, and the installation is convenient.

On the basis of the above embodiments, in some specific embodiments of the present invention, the periphery of the bottom of the sensor housing 1 is provided with the first external conical surface 11 for signal transmission, the inner wall of the bottom of the sensor housing 1 is further provided with the first internal conical surface 12, and the periphery of the first end of the circuit board 2 is provided with the first external conical surface 21 matched with the first internal conical surface 12. In this embodiment, when the bottom of the sensor housing 1 is installed at the measured position, the sensing area of the sensor probe can be increased by arranging the first outer conical surface 11, which is beneficial to improving the signal monitoring effect. And through the cooperation of first internal conical surface 12 and first external conical surface 21, not only can make things convenient for the assembly of sensor housing 1 with circuit board 2, help sensor housing 1 to transmit physical quantities such as vibration and impact signal received to the sensing element on the circuit board 2 subassembly simultaneously to further improve sensor probe's signal monitoring sensitivity. Further, on the basis of the above embodiment, in a specific implementation manner, the first end of the circuit board 2 is provided with a step plate 22 for welding the temperature measuring element pin, the thickness of the step plate 22 is smaller than that of the circuit board 2 itself, and the first end of the gland 3 abuts against the second end of the circuit board 2. In this embodiment, a temperature measuring element generally needs to be installed inside the sensor probe, and the step plate 22 is disposed at the first end of the circuit board 2, so that the pin of the temperature measuring element 25 can be soldered on the step plate 22. When the circuit board 2 is mounted, the first end of the circuit board is inserted into the bottom of the sensor housing 1, and the other end of the circuit board abuts against the first end of the gland 3, so that the circuit board 2 can be axially fixed. At this time, since the thickness of the step plate 22 is smaller than the thickness of the circuit board 2 itself, after the temperature measuring element 25 is mounted, the distance between the pin and the sensor housing 1 can be increased, so as to ensure a sufficient insulation distance and improve the insulation performance of the sensor.

Further, on the basis of the above-mentioned embodiments, in some alternative embodiments, the inner wall of the middle portion of the sensor housing 1 is provided with the guide groove 13, and the outer periphery of the second end of the circuit board 2 is provided with the protrusion 23 which is matched with the guide groove 13. In this embodiment, through the cooperation of guide slot 13 and protruding 23, not only can make things convenient for positioning circuit board 2, can improve the uniformity of sensor probe sensitivity moreover.

Further, on the basis of the above embodiments, in some alternative embodiments, the first end of the pressing cover 3 is provided with a bayonet, and the second end of the circuit board 2 is provided with a limiting step 24 matched with the bayonet. In this embodiment, through the cooperation of bayonet socket and spacing step 24, can radially fix circuit board 2, improve circuit board 2's fixed effect.

In the above embodiments, some of the assembling manners of the sensor housing 1 and the circuit board 2 are explained, and the other assembling manners are explained by the embodiments below.

Referring to fig. 7 to 10, the circuit board 2 includes a horizontal plate 201 mounted on the bottom of the sensor housing 1 and a vertical plate 202 fixed to the horizontal plate 201. In this embodiment, the circuit board 2 includes a horizontal plate 201 and a vertical plate 202, and when it is necessary to sense a vibration impact signal in a horizontal direction, the sensing element may be mounted on the vertical plate 202, and when it is necessary to sense a vibration impact signal in a vertical direction, the sensing element may be mounted on the horizontal plate 201, and by combining the horizontal plate 201 and the vertical plate 202, mounting of sensing elements in different axial directions may be achieved.

During specific implementation, the horizontal plate 201 and the vertical plate 202 can be fixed by welding, after the circuit board 2 is inserted into the inner cavity of the sensor housing 1, the horizontal plate 201 is installed at the bottom of the sensor housing 1, and the gland 3 compresses the vertical plate 202, so that the axial fixation of the circuit board 2 is realized.

Further, on the basis of the above-mentioned embodiments, in a preferred embodiment, the inner cavity of the sensor housing 1 is provided with a sleeve 8, a first end of the sleeve 8 abuts against the horizontal plate 201, and a second end of the sleeve 8 abuts against the gland 3. In this embodiment, after the circuit board 2 is mounted, the pressing cover 3 presses the horizontal plate 201 through the sleeve 8, so as to axially fix the circuit board 2. When the processing circuit for processing the electric signal output by the sensing element is mounted on the vertical plate 202, the vertical plate 202 is not stressed when the pressing cover 3 axially presses the circuit board 2, so that the service life of the electric element can be prolonged.

In specific implementation, because the vertical plate 202 can not be stressed, the horizontal plate 201 and the vertical plate 202 can be fixed through clamping, and the assembly and disassembly are convenient. Further, on the basis of the above-mentioned embodiment, in a preferred embodiment, the inner wall of the bottom of the sensor housing 1 is provided with a second inner conical surface 14, the horizontal plate 201 includes a first horizontal circular plate and a second horizontal circular plate corresponding to the second inner conical surface 14, the first end of the sleeve 8 abuts against the first horizontal circular plate, and the diameter of the first horizontal circular plate is larger than that of the second horizontal circular plate. In this embodiment, the inner wall of the bottom of the sensor housing 1 is provided with a second inner conical surface 14, the horizontal plate 201 includes a first horizontal circular plate and a second horizontal circular plate which are coaxial, wherein the diameter of the first horizontal circular plate is larger than that of the second horizontal circular plate, both the first horizontal circular plate and the second horizontal circular plate can be adapted to the second inner conical surface 14, the first end of the sleeve 8 abuts against the first horizontal circular plate, and the sensing element can be mounted on the second horizontal circular plate. After the circuit board 2 is installed, the first horizontal circular plate and the second horizontal circular plate are designed, so that the fixing effect of the circuit board 2 can be further improved, and the sensor housing 1 is facilitated to transmit physical quantities such as received vibration and impact signals to the sensitive element on the circuit board 2. As a preferred embodiment of the invention, the outside of the cable 7 is provided with a hose for protection. In this embodiment, the hose has good flexibility and fatigue resistance, can absorb cyclic loads of various motion deformations, and particularly has the capability of compensating for large displacement in measuring mechanical vibration, so that the hose is arranged outside the cable 7, and the waterproof and dustproof effects of the cable 7 can be further improved.

Further, on the basis of the foregoing embodiments, in a specific implementation manner, the circuit board 2 is mounted with a sensor 26 and a signal conditioning circuit, the sensor 26 is configured to sense a physical quantity of a vibration impact at a measured position and convert the physical quantity into a charge signal, and the signal conditioning circuit is configured to convert the charge signal output by the sensor 26 into a voltage signal and amplify the voltage signal.

In the embodiment of the present invention, the sensing element 26 mounted on the circuit board 2 can sense the physical quantity of vibration impact at the measured position and convert the physical quantity into a charge signal; however, considering that the charge signals output by the sensor vibration impact sensitive element are weak and are easily interfered, the circuit board 2 is further provided with a signal conditioning circuit for converting the charge signals output by the sensitive element 26 into voltage signals and amplifying the voltage signals, so that the anti-interference capability of signal transmission is improved, and the acquisition of a post-stage acquisition circuit is facilitated. Optionally, a shielding cover is disposed outside the signal conditioning circuit to shield interference, so as to further improve stability of signal transmission.

Referring to fig. 11 to fig. 16, on the basis of the above embodiments, in a specific implementation, the signal conditioning circuit includes a first charge amplifying module 271, a second charge amplifying module 272 and a differential amplifying module 273;

the input end of the first charge amplification module 271 and the input end of the second charge amplification module 272 are respectively connected to two ends of the sensor 26, and are used for converting the charge signal output by the sensor 26 into a voltage signal;

the first input end and the second input end of the differential amplification module 273 are respectively connected to the output end of the first charge amplification module 271 and the output end of the second charge amplification module 272, and the output end of the differential amplification module 273 is connected to the input end of the rear-stage detection system, and is configured to differentially amplify the voltage signals output by the first charge amplification module 271 and the second charge amplification module 272.

Specifically, on the basis of the above embodiments, in some optional embodiments of the present invention, the first charge amplifying module 271 includes a first operational amplifier, a first capacitor, a first resistor and a second resistor, and the second charge amplifying module 272 includes a second operational amplifier, a second capacitor, a third resistor and a fourth resistor;

the inverting input end of the first operational amplifier is used as the input end of the first charge amplification module 271, the non-inverting input end of the first operational amplifier is connected to the reference voltage, the output end of the first operational amplifier is used as the output end of the first charge amplification module 272, two ends of the first capacitor are respectively connected to the inverting input end of the first operational amplifier and the output end of the first operational amplifier, the first end of the first resistor is connected to the inverting input end of the first operational amplifier, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the output end of the first operational amplifier;

the inverting input end of the second operational amplifier is used as the input end of the second charge amplification module 272, the non-inverting input end of the second operational amplifier is connected with the reference voltage, the output end of the second operational amplifier is used as the output end of the second charge amplification module 272, two ends of the second capacitor are respectively connected with the inverting input end of the second operational amplifier and the output end of the second operational amplifier, the first end of the third resistor is connected with the inverting input end of the second operational amplifier, the second end of the third resistor is connected with the first end of the fourth resistor, and the second end of the fourth resistor is connected with the output end of the second operational amplifier.

In the embodiment of the present invention, the first charge amplification module 271 comprises a first operational amplifier N1A, a first capacitor C1, a first resistor R1 and a second resistor R2, and the second charge amplification module 272 comprises a second operational amplifier N1B, a second capacitor C2, a third resistor R3 and a fourth resistor R4. The non-inverting input ends of the first operational amplifier N1A and the second operational amplifier N1B are both connected to the reference voltage VDD, the inverting input ends of the first operational amplifier N1A and the second operational amplifier N1B are respectively connected to two ends of the sensor 26, and the output ends of the first operational amplifier N1A and the second operational amplifier N1B are respectively connected to the first input end and the second input end of the differential amplification module 273; a first capacitor C1 and a second capacitor C2 are used for realizing charge-to-voltage conversion, wherein the first capacitor C1 is connected between the inverting input terminal of the first operational amplifier N1A and the output terminal of the first operational amplifier N1A, and the second capacitor C1 is connected between the inverting input terminal of the second operational amplifier N1B and the output terminal of the first operational amplifier N1A; the first resistor R1 and the second resistor R2 are connected in series and then are connected in parallel to two ends of the first capacitor C1, and the first resistor R1 and the second resistor R2 are used for guaranteeing normal static operation of the first operational amplifier N1A; the third resistor R3 and the fourth resistor R4 are connected in series and then connected in parallel to two ends of the second capacitor C2, so as to ensure that the second operational amplifier N1B works normally in a static state.

Further, on the basis of the above embodiments, in some alternative embodiments, the differential amplifying module 273 includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a third operational amplifier; a first end of the fifth resistor is used as a first input end of the differential amplifying module 273, a second end of the fifth resistor is connected to a first end of the sixth resistor and an inverting input end of the third operational amplifier, respectively, a second end of the sixth resistor is connected to the reference voltage, a first end of the seventh resistor is used as a second input end of the differential amplifying module 273, a second end of the seventh resistor is connected to a first end of the eighth resistor and a non-inverting input end of the third operational amplifier, respectively, a second end of the eighth resistor is connected to an output end of the third operational amplifier, and a common end of the eighth resistor is used as an output end of the differential amplifying module 273.

In the embodiment of the present invention, the differential amplifying module 273 comprises two sets of symmetrical fifth resistor R5, sixth resistor R6, seventh resistor R7, eighth resistor R8 and third operational amplifier N1C. A first end of the fifth resistor R5 and a first end of the seventh resistor R7 are respectively connected to the output end of the first charge amplification module 271 and the output end of the second charge amplification module 272, and a second end of the fifth resistor R5 and a second end of the seventh resistor R7 are respectively connected to the inverting input end of the third operational amplifier N1C and the non-inverting input end of the third operational amplifier N1C; a first end of the sixth resistor R6 is connected to the reference voltage VDD, and a second end of the sixth resistor R6 is connected to a connection node between a second end of the fifth resistor R5 and the inverting input terminal of the third operational amplifier N1C; a first end of the eighth resistor R8 is connected to a connection node between a second end of the seventh resistor R7 and the non-inverting input terminal of the third operational amplifier N1C, a second end of the eighth resistor R8 is connected to the output terminal of the third operational amplifier N1C, and a common terminal of the eighth resistor R8 is connected to the input terminal of the post-detection system; the positive power supply end of the third operational amplifier N1C is connected to the power supply voltage VCC, and the ground end of the third operational amplifier N1C is grounded.

Further, on the basis of the foregoing embodiments, in some optional embodiments, the signal conditioning circuit further includes a bootstrap module 274, configured to boost the voltage of the voltage signal output by the first charge amplification module 271 and the second charge amplification module 272. In this embodiment, considering that the gain of the sensor 26 is too small in the low frequency range, the bootstrap module 274 is designed between the first charge amplification module 271 and the second charge amplification module 272, so as to boost the voltage of the voltage signal output by the first charge amplification module 271 and the second charge amplification module 272.

Optionally, on the basis of the foregoing embodiment, in a specific implementation manner, the bootstrap module 274 includes a ninth resistor, a tenth resistor, and a third capacitor; the first end of the ninth resistor is connected with the connection node of the second end of the first resistor and the first end of the second resistor, the second end of the ninth resistor is connected with the first end of the third capacitor, the second end of the third capacitor is connected with the first end of the tenth resistor, and the second end of the tenth resistor is connected with the connection node of the second end of the third resistor and the first end of the fourth resistor.

In the embodiment of the present invention, the bootstrap module 274 is composed of a ninth resistor R9, a tenth resistor R10 and a third capacitor C3. The ninth resistor R9 and the tenth resistor R10 are both current-limiting resistors, the first end of the ninth resistor R9 is connected between the first resistor R1 and the second resistor R2, and the second end of the ninth resistor R9 is connected with one end of the third capacitor C3; a first end of the tenth resistor R10 is connected between the third resistor R3 and the fourth resistor R4, and a second end of the tenth resistor R10 is connected to the other end of the third capacitor C3; the third capacitor C3 is a bootstrap capacitor, and is used to boost the voltage of the voltage signals output by the first charge amplification module 271 and the second charge amplification module 272, so as to compensate the shortage that the gain of the sensing element 26 is too small in the low frequency range.

Optionally, in another specific embodiment, the bootstrap module 274 includes an eleventh resistor and a fourth capacitor; the first end of the eleventh resistor is connected with a connection node between the second end of the first resistor and the first end of the second resistor, the second end of the eleventh resistor is connected with the first end of the fourth capacitor, and the second end of the fourth capacitor is connected with a connection node between the second end of the third resistor and the first end of the fourth resistor. In this embodiment, the bootstrap module 274 is composed of an eleventh resistor R11 and a fourth capacitor C4. As a preferred embodiment of the present invention, the signal conditioning circuit further includes an anti-interference module 275 for improving the anti-interference capability of the sensing element 26. In this embodiment, the anti-interference modules 275 are designed at two ends of the sensing element 26, so that the anti-interference capability of the sensing element 26 can be effectively improved.

Further, on the basis of the foregoing embodiment, in a specific implementation manner, the anti-interference module 275 includes a twelfth resistor, a thirteenth resistor, a fifth capacitor, and a sixth capacitor, where a first end of the twelfth resistor is connected to the first end of the sensing element 26 and the first end of the fifth capacitor, a second end of the twelfth resistor is connected to the first end of the thirteenth resistor, a second end of the thirteenth resistor is connected to the second end of the sensing element 26 and the first end of the sixth capacitor, a common end of the twelfth resistor and the thirteenth resistor is connected to the reference voltage, a second end of the fifth capacitor is connected to the input end of the first charge amplification module 271, and a second end of the sixth capacitor is connected to the input end of the second charge amplification module 272.

In the embodiment of the present invention, the anti-interference module 275 is composed of a twelfth resistor R12, a thirteenth resistor R13, a fifth capacitor C5 and a sixth capacitor C6. The twelfth resistor R12 and the thirteenth resistor R13 are connected in series to two ends of the sensor 26, a common terminal of the twelfth resistor R12 and the thirteenth resistor R13 is connected to the reference voltage VDD, the fifth capacitor C5 is connected in series between the first terminal of the sensor 26 and the input terminal of the first charge amplification module 271, and the sixth capacitor C6 is connected in series between the second terminal of the sensor 26 and the input terminal of the second charge amplification module 272, so that the anti-interference capability of the sensor 26 can be effectively improved.

Optionally, in another specific embodiment, the anti-interference module 275 includes a fourteenth resistor, a seventh capacitor and an eighth capacitor, where a first end of the fourteenth resistor is connected to the first end of the sensing element 26 and the first end of the seventh capacitor, a second end of the fourteenth resistor is connected to the second end of the sensing element 26 and the first end of the eighth capacitor, a second end of the seventh capacitor is connected to the input end of the first charge amplification module 271, and a second end of the eighth capacitor is connected to the input end of the second charge amplification module 272. In this embodiment, the interference rejection module 275 includes a fourteenth resistor R14, a seventh capacitor C7, and an eighth capacitor C8.

As a preferred embodiment of the present invention, the signal conditioning circuit further comprises a first power processing module 276; the input end of the first power processing module 276 is connected to an input power, the first output end of the first power processing module 276 is used for providing a power voltage, and the second output end of the first power processing module 276 is used for providing a reference voltage.

The embodiment of the utility model provides an in, for the stability of guaranteeing signal conditioning circuit, consequently increased first power processing module 276 in signal conditioning circuit, its input inserts external input power, and first output provides stable mains voltage for signal conditioning circuit, and the second output provides stable reference voltage for signal conditioning circuit to improve reference voltage's precision.

Specifically, in the above embodiment, the first power processing module 276 includes a diode, a fifteenth resistor, a ninth capacitor, a tenth capacitor, and a first voltage regulator; the anode of the diode is used as the input end of the first power processing module 276, the cathode of the diode is connected to the first end of the fifteenth resistor and the first end of the ninth capacitor, respectively, the common end of the diode is used as the first output end of the first power processing module 276, the second end of the fifteenth resistor is connected to the first end of the tenth capacitor and the cathode of the first voltage regulator tube, respectively, the common end of the diode is used as the second output end of the first power processing module 276, and the second end of the ninth capacitor, the second end of the tenth capacitor and the anode of the first voltage regulator tube are all connected to ground.

In the embodiment of the present invention, the first power processing module 276 is composed of a diode V1, a fifteenth resistor R15, a ninth capacitor C9, a tenth capacitor C10, and a first voltage regulator tube Z1; the diode V1 is an anti-reverse diode, and the anode of the diode V1 is connected with an external input power supply; the ninth capacitor C9 is a filter capacitor, and has a first terminal connected to the cathode of the diode V1 and a second terminal connected to ground; a connection node between the cathode of the diode V1 and the first end of the ninth capacitor C9 outputs a power supply voltage VCC which supplies power to a positive power supply end of an operational amplifier in the signal conditioning circuit; the fifteenth resistor R15 is a current-limiting resistor for limiting the maximum current flowing through the first regulator tube Z1, and has a first end connected to the connection node between the cathode of the diode V1 and the first end of the ninth capacitor C9; a tenth capacitor C10 is a filter capacitor, a first voltage regulator tube Z1 is a voltage regulator diode, the first end of the tenth capacitor C10 and the cathode of the first voltage regulator tube Z1 are both connected with the second end of a fifteenth resistor R15, and the first end of the tenth capacitor C10 and the anode of the first voltage regulator tube Z1 are both connected with the ground; the connection node between the second terminal of the fifteenth resistor R15, the first terminal of the tenth capacitor C10, and the cathode of the first regulator tube Z1 outputs the reference voltage VDD, which provides the reference voltage for the first charge amplification module 271, the second charge amplification module 272, the differential amplification module 273, and the like. Optionally, the sensing element 26 may also be powered by the reference voltage VDD; when the temperature measuring element arranged in the sensor outputs analog signals such as a platinum resistor temperature sensitive device, the temperature measuring element outputting the analog signals can also be directly powered by the reference voltage VDD.

Further, on the basis of the above embodiments, in some optional embodiments, the signal conditioning circuit further includes a second power processing module 277; the input end of the second power processing module 277 is connected to the second output end of the first power processing module 276, and the output end of the second power processing module 277 is used for supplying power to the temperature measuring element.

In the embodiment of the present invention, the temperature measuring element installed inside the sensor is considered to be possibly the digital signal output, and the sensing element 26 is the analog signal output, so as to avoid mutual interference, and therefore, the second power processing module 277 is further added to the signal conditioning circuit, the input end of the second power processing module is connected to the second output end of the first power processing module 276, and the output end of the second power processing module is used for supplying power to the temperature measuring element of the digital signal output.

Optionally, in a specific embodiment, the second power processing module 277 includes a sixteenth resistor, an eleventh capacitor, and a second voltage regulator; the first end of the sixteenth resistor is used as the input end of the second power processing module 277, the second end of the sixteenth resistor is respectively connected with the first end of the eleventh capacitor and the cathode of the second voltage regulator tube, the common end of the sixteenth resistor is used as the output end of the second power processing module 277, and the second end of the eleventh capacitor and the anode of the second voltage regulator tube are both connected with the ground.

In the embodiment of the present invention, the second power processing module 277 includes a sixteenth resistor R16, an eleventh capacitor C11, and a second voltage regulator tube Z2; the sixteenth resistor R16 is a current-limiting resistor for limiting the maximum current flowing through the second voltage regulator tube Z2, and the first end of the sixteenth resistor R16 is connected to the reference voltage VDD; an eleventh capacitor C11 is a filter capacitor, a second voltage regulator tube Z2 is a voltage regulator diode, a first end of the eleventh capacitor C11 and a cathode of the second voltage regulator tube Z2 are both connected with a second end of a sixteenth resistor R16, and a first end of the eleventh capacitor C11 and an anode of the second voltage regulator tube Z2 are both connected with the ground; and the connection node of the second end of the sixteenth resistor R16, the first end of the eleventh capacitor C11 and the cathode of the second voltage regulator tube Z2 is used as the output end of the second power processing module 277 and supplies power for the temperature measuring element for outputting digital signals. That is to say, in this embodiment, the reference voltage VDD supplies power to the temperature measuring element outputting the digital signal after passing through the separate voltage stabilizing circuit, and the circuit is simple and has low cost.

Optionally, in another specific embodiment, the second power processing module 277 includes a fourth operational amplifier, a seventeenth resistor, and a twelfth capacitor; the non-inverting input terminal of the fourth operational amplifier is used as the input terminal of the second power processing module 277, the inverting input terminal of the fourth operational amplifier is connected to the output terminal of the fourth operational amplifier and the first terminal of the seventeenth resistor, the second terminal of the seventeenth resistor is connected to the first terminal of the twelfth capacitor, the common terminal of the seventeenth resistor is used as the output terminal of the second power processing module 277, and the second terminal of the twelfth capacitor is connected to ground.

In the embodiment of the present invention, the second power processing module 277 includes a fourth operational amplifier N1D, a seventeenth resistor R17, and a twelfth capacitor C12; the fourth operational amplifier N1D is used as a voltage follower, the non-inverting input terminal of the fourth operational amplifier is connected to the reference voltage VDD, and the inverting input terminal of the fourth operational amplifier is short-circuited with the output terminal; the seventeenth resistor R17 is a current-limiting resistor, and has a first end connected to the node connecting the inverting input terminal and the output terminal of the fourth operational amplifier N1D; the twelfth capacitor C12 is a filter capacitor, and has a first end connected to the second end of the seventeenth resistor R17, and a second end connected to ground; the connection node of the second end of the seventeenth resistor R17 and the first end of the twelfth capacitor C12 serves as the output end of the second power processing module 277 and supplies power to the temperature measuring element outputting the digital signal. That is to say, in this embodiment, the reference voltage VDD supplies power to the temperature measuring element outputting the digital signal after passing through the voltage follower circuit, so as to realize voltage follower and improve the driving capability.

As a preferred embodiment of the present invention, the signal conditioning circuit further comprises an electrostatic protection module for providing electrostatic protection; the electrostatic protection module comprises a first electrostatic discharge tube, a second electrostatic discharge tube, a third electrostatic discharge tube and a fourth electrostatic discharge tube; the first end of the first electrostatic discharge tube is connected to the input end of the first power processing module 276, the first end of the second electrostatic discharge tube is connected to the second output end of the first power processing module 276, the first end of the third electrostatic discharge tube is connected to the output end of the differential amplification module 273, the first end of the fourth electrostatic discharge tube is connected to the output end of the temperature measuring element, and the second end of the first electrostatic discharge tube, the second end of the second electrostatic discharge tube, the second end of the third electrostatic discharge tube and the second end of the fourth electrostatic discharge tube are all connected to the ground.

The embodiment of the utility model provides an in, in order to improve signal conditioning circuit's antistatic capacity, still designed the electrostatic protection module in signal conditioning circuit, can provide electrostatic protection. Specifically, the electrostatic protection module includes a first electrostatic discharge tube ESD1, a second electrostatic discharge tube ESD2, a third electrostatic discharge tube ESD3, and a fourth electrostatic discharge tube ESD 4; the first end of the first electrostatic discharge tube ESD1 is connected to the input end of the first power processing module 276, the first end of the second electrostatic discharge tube ESD2 is connected to the second output end of the first power processing module 276, the first end of the third electrostatic discharge tube ESD3 is connected to the output end of the differential amplification module 273, the first end of the fourth electrostatic discharge tube ESD4 is connected to the output end of the temperature measuring element, and the second ends of the first electrostatic discharge tube ESD1, the second electrostatic discharge tube ESD2, the third electrostatic discharge tube ESD3 and the fourth electrostatic discharge tube ESD4 are all connected to ground, so as to perform electrostatic protection on the power input interface, the reference voltage output interface, the sensitive element output interface and the temperature measuring element output interface. Optionally, when the encoder chip is installed inside the sensor, the first end of the second electrostatic discharge tube ESD2 may be selectively connected to the output end of the encoder chip, so as to perform electrostatic protection on the output interface of the encoder chip.

Optionally, a resistor R18 is connected between the input end of the first charge amplification module 271 and the first end of the sensor 26, and a resistor R19 is connected between the input end of the second charge amplification module 272 and the second end of the sensor 26, so that the interference immunity of the input signals of the first charge amplification module 271 and the second charge amplification module 272 can be improved.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (23)

1. The utility model provides a sensor probe, its characterized in that includes sensor housing, circuit board, gland, pressure cap, clamping ring and is located the intra-annular seal cover of clamping ring, the circuit board install in sensor housing's inner chamber, the surface of the first end of gland with the inner wall cooperation at sensor housing's top is connected, the inner wall of the second end of gland with the outer wall cooperation of pressure cap compresses tightly with the axial the clamping ring, the clamping ring and then the axial compresses tightly the seal cover, the center of gland, pressure cap, clamping ring, seal cover all is equipped with the through-hole that is used for the cable to pass.

2. The sensor probe of claim 1, wherein the outer perimeter of the bottom of the sensor housing defines a first outer tapered surface for signal transmission, the inner wall of the bottom of the sensor housing defines a first inner tapered surface, and the outer perimeter of the first end of the circuit board defines a second outer tapered surface that mates with the first inner tapered surface.

3. The sensor probe of claim 1, wherein the first end of the circuit board is provided with a step plate for soldering the temperature measuring element pin, the thickness of the step plate is smaller than the thickness of the circuit board itself, and the first end of the gland abuts against the second end of the circuit board.

4. The sensor probe of claim 1, wherein the inner wall of the middle portion of the sensor housing is provided with a guide groove, and the outer circumference of the second end of the circuit board is provided with a protrusion engaged with the guide groove.

5. The sensor probe of claim 4, wherein the first end of the gland is provided with a bayonet and the second end of the circuit board is provided with a limiting step which is matched with the bayonet.

6. The sensor probe of claim 1, wherein the circuit board comprises a horizontal plate mounted to the bottom of the sensor housing and a vertical plate secured to the horizontal plate.

7. The sensor probe of claim 6, wherein the inner cavity of the sensor housing is provided with a sleeve, a first end of the sleeve abuts against the horizontal plate, and a second end of the sleeve abuts against the gland.

8. The sensor probe of claim 7, wherein the inner wall of the bottom of the sensor housing has a second inner conical surface, the horizontal plate comprises a first horizontal circular plate and a second horizontal circular plate corresponding to the second inner conical surface, the first end of the sleeve abuts against the first horizontal circular plate, and the diameter of the first horizontal circular plate is larger than that of the second horizontal circular plate.

9. The sensor probe of any one of claims 1 to 8, wherein a sensing element and a signal conditioning circuit are mounted on the circuit board, the sensing element is used for sensing the vibration impact physical quantity of the measured position and converting the vibration impact physical quantity into a charge signal, and the signal conditioning circuit is used for converting the charge signal output by the sensing element into a voltage signal.

10. The sensor probe of claim 9, wherein the signal conditioning circuit comprises a first charge amplification module, a second charge amplification module, and a differential amplification module;

the input end of the first charge amplification module and the input end of the second charge amplification module are respectively connected with two ends of the sensitive element and are used for converting the charge signal output by the sensitive element into a voltage signal;

the first input end and the second input end of the differential amplifying module are respectively connected with the output end of the first charge amplifying module and the output end of the second charge amplifying module, and the output end of the differential amplifying module is connected with the input end of a rear-stage detection system and used for differentially amplifying voltage signals output by the first charge amplifying module and the second charge amplifying module.

11. The sensor probe of claim 10, wherein the first charge amplification module comprises a first operational amplifier, a first capacitor, a first resistor, and a second resistor, and the second charge amplification module comprises a second operational amplifier, a second capacitor, a third resistor, and a fourth resistor;

the inverting input end of the first operational amplifier is used as the input end of the first charge amplification module, the non-inverting input end of the first operational amplifier is connected with a reference voltage, the output end of the first operational amplifier is used as the output end of the first charge amplification module, two ends of the first capacitor are respectively connected with the inverting input end of the first operational amplifier and the output end of the first operational amplifier, the first end of the first resistor is connected with the inverting input end of the first operational amplifier, the second end of the first resistor is connected with the first end of the second resistor, and the second end of the second resistor is connected with the output end of the first operational amplifier;

the inverting input end of the second operational amplifier is used as the input end of the second charge amplification module, the non-inverting input end of the second operational amplifier is connected to the reference voltage, the output end of the second operational amplifier is used as the output end of the second charge amplification module, two ends of the second capacitor are respectively connected with the inverting input end of the second operational amplifier and the output end of the second operational amplifier, the first end of the third resistor is connected with the inverting input end of the second operational amplifier, the second end of the third resistor is connected with the first end of the fourth resistor, and the second end of the fourth resistor is connected with the output end of the second operational amplifier;

the differential amplification module comprises a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor and a third operational amplifier;

a first end of the fifth resistor is used as a first input end of the differential amplification module, a second end of the fifth resistor is respectively connected with a first end of the sixth resistor and an inverting input end of the third operational amplifier, a second end of the sixth resistor is connected to the reference voltage, a first end of the seventh resistor is used as a second input end of the differential amplification module, a second end of the seventh resistor is respectively connected with a first end of the eighth resistor and a non-inverting input end of the third operational amplifier, a second end of the eighth resistor is connected with an output end of the third operational amplifier, and a common end of the eighth resistor is used as an output end of the differential amplification module.

12. The sensor probe of claim 11, wherein the signal conditioning circuit further comprises a bootstrap module for boosting the voltage of the voltage signals output by the first and second charge amplification modules.

13. The sensor probe of claim 12, wherein the bootstrap module includes a ninth resistance, a tenth resistance, and a third capacitance;

the first end of the ninth resistor is connected with the connection node of the second end of the first resistor and the first end of the second resistor, the second end of the ninth resistor is connected with the first end of the third capacitor, the second end of the third capacitor is connected with the first end of the tenth resistor, and the second end of the tenth resistor is connected with the connection node of the second end of the third resistor and the first end of the fourth resistor.

14. The sensor probe of claim 12, wherein the bootstrap module includes an eleventh resistor and a fourth capacitor;

the first end of the eleventh resistor is connected with a connection node between the second end of the first resistor and the first end of the second resistor, the second end of the eleventh resistor is connected with the first end of the fourth capacitor, and the second end of the fourth capacitor is connected with a connection node between the second end of the third resistor and the first end of the fourth resistor.

15. The sensor probe of claim 11, wherein the signal conditioning circuit further comprises an anti-jamming module for enhancing the anti-jamming capability of the sensing element.

16. The sensor probe of claim 15, wherein the immunity module includes a twelfth resistor, a thirteenth resistor, a fifth capacitor, and a sixth capacitor;

a first end of the twelfth resistor is connected to the first end of the sensing element and the first end of the fifth capacitor, a second end of the twelfth resistor is connected to the first end of the thirteenth resistor, a second end of the thirteenth resistor is connected to the second end of the sensing element and the first end of the sixth capacitor, a common terminal of the twelfth resistor and the thirteenth resistor is connected to the reference voltage, a second end of the fifth capacitor is connected to the input terminal of the first charge amplification module, and a second end of the sixth capacitor is connected to the input terminal of the second charge amplification module.

17. The sensor probe of claim 15, wherein the immunity module includes a fourteenth resistor, a seventh capacitor, and an eighth capacitor;

a first end of the fourteenth resistor is connected to the first end of the sensing element and the first end of the seventh capacitor, a second end of the fourteenth resistor is connected to the second end of the sensing element and the first end of the eighth capacitor, a second end of the seventh capacitor is connected to the input end of the first charge amplification module, and a second end of the eighth capacitor is connected to the input end of the second charge amplification module.

18. The sensor probe of claim 11, wherein the signal conditioning circuit further comprises a first power processing module;

the input end of the first power supply processing module is connected with an input power supply, the first output end of the first power supply processing module is used for providing power supply voltage, and the second output end of the first power supply processing module is used for providing the reference voltage.

19. The sensor probe of claim 18, wherein the first power processing module comprises a diode, a fifteenth resistor, a ninth capacitor, a tenth capacitor, and a first voltage regulator;

the anode of the diode is used as the input end of the first power processing module, the cathode of the diode is respectively connected with the first end of the fifteenth resistor and the first end of the ninth capacitor, the common end of the diode is used as the first output end of the first power processing module, the second end of the fifteenth resistor is respectively connected with the first end of the tenth capacitor and the cathode of the first voltage regulator tube, the common end of the fifteenth resistor is used as the second output end of the first power processing module, and the second end of the ninth capacitor, the second end of the tenth capacitor and the anode of the first voltage regulator tube are all connected with the ground.

20. The sensor probe of claim 19, wherein the signal conditioning circuit further comprises a second power processing module;

the input end of the second power supply processing module is connected with the second output end of the first power supply processing module, and the output end of the second power supply processing module is used for supplying power to the temperature measuring element.

21. The sensor probe of claim 20, wherein the second power processing module comprises a sixteenth resistor, an eleventh capacitor, and a second voltage regulator;

and a first end of the sixteenth resistor is used as an input end of the second power supply processing module, a second end of the sixteenth resistor is respectively connected with a first end of the eleventh capacitor and a cathode of the second voltage-stabilizing tube, a common end of the sixteenth resistor is used as an output end of the second power supply processing module, and a second end of the eleventh capacitor and an anode of the second voltage-stabilizing tube are both connected with the ground.

22. The sensor probe of claim 20, wherein the second power processing module comprises a fourth operational amplifier, a seventeenth resistor, and a twelfth capacitor;

the non-inverting input end of the fourth operational amplifier is used as the input end of the second power supply processing module, the inverting input end of the fourth operational amplifier is respectively connected with the output end of the fourth operational amplifier and the first end of the seventeenth resistor, the second end of the seventeenth resistor is connected with the first end of the twelfth capacitor, the common end of the seventeenth resistor is used as the output end of the second power supply processing module, and the second end of the twelfth capacitor is connected with the ground.

23. The sensor probe of claim 18, wherein the signal conditioning circuit further comprises an electrostatic protection module for providing electrostatic protection;

the electrostatic protection module comprises a first electrostatic discharge tube, a second electrostatic discharge tube, a third electrostatic discharge tube and a fourth electrostatic discharge tube;

the first end of the first electrostatic discharge tube is connected with the input end of the first power supply processing module, the first end of the second electrostatic discharge tube is connected with the second output end of the first power supply processing module, the first end of the third electrostatic discharge tube is connected with the output end of the differential amplification module, the first end of the fourth electrostatic discharge tube is connected with the output end of the temperature measuring element, and the second end of the first electrostatic discharge tube, the second end of the second electrostatic discharge tube, the second end of the third electrostatic discharge tube and the second end of the fourth electrostatic discharge tube are all connected with the ground.

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