CN114900170A

CN114900170A - Contactless proximity switch

Info

Publication number: CN114900170A
Application number: CN202210503916.3A
Authority: CN
Inventors: 许生平
Original assignee: Wenzhou Dongtou Yalixi Electronic And Electrical Control Equipment Co Ltd
Current assignee: Wenzhou Dongtou Yalixi Electronic And Electrical Control Equipment Co Ltd
Priority date: 2022-05-10
Filing date: 2022-05-10
Publication date: 2022-08-12

Abstract

The invention relates to a contactless proximity switch, which comprises an EM mechanism for generating an electromagnetic field, a monitoring circuit for monitoring the change of the electromagnetic field and a processor, wherein the EM mechanism comprises a plurality of different electronic components, the electronic components are respectively communicated with the monitoring circuit, the output signal of the monitoring circuit is electrically connected with the processor, and the processor comprises a processing unit for processing a plurality of output signals and a control unit for controlling different electronic components. By adopting the technical scheme, the magnetic field interference caused by environmental factors can be reduced, the condition that the switch cannot be operated is avoided, the repeated positioning precision is high, the anti-interference performance is good, the high temperature resistance and the water resistance are realized, meanwhile, the arrangement of multiple electronic components increases the induction distance, the switch can be used in complex environments such as underwater and the like, and can be applied to the fields such as steel, traffic, mines, military industry and the like, and the application range of the switch is expanded.

Description

Contactless proximity switch

Technical Field

The invention relates to the technical field of sensors, in particular to a contactless proximity switch.

Background

The proximity switch is a position switch which can be operated without mechanical direct contact with a moving part, and when the sensing surface of the object proximity switch reaches an action distance, the switch can be actuated without mechanical contact and any pressure applied, so that a direct current electric appliance is driven or a control instruction is provided for a computer (plc) device. The approach switch is a switch type sensor (i.e. a non-contact switch), which has the characteristics of a travel switch and a microswitch, and has the characteristics of sensing performance, reliable action, stable performance, fast frequency response, long service life, strong anti-interference capability and the like, and has the characteristics of water resistance, shock resistance, corrosion resistance and the like. The product has inductance type, capacitance type, Hall type, AC type and DC type.

The proximity switch is also called contactless proximity switch, and is an ideal electronic switching value sensor. When the metal detection body approaches to the induction area of the switch, the switch can send out an electric command rapidly without contact, pressure and spark, and accurately reflect the position and the stroke of the motion mechanism. It is widely used in machine tool, metallurgy, chemical industry, light textile and printing industries. The automatic control system can be used as the links of limiting, counting, positioning control, automatic protection and the like.

The proximity switch principle is that the magnetic field intensity is changed by adjusting the current on the coil, and whether a metal object exists or not is identified by the eddy current effect principle. The current general setting method is to change the resistance of the resistor on the control board, so as to change the current flowing through the coil to set the distance.

However, increasing Q by decreasing the resistance of the inductive element only slightly increases the inductive distance, because the key of the inductive distance is not solved, and the existing proximity switch can only sense a metal inductor, which has limitations.

Disclosure of Invention

In summary, in order to overcome the defects of the prior art, the invention provides a contactless proximity switch.

In order to achieve the purpose, the invention provides the following technical scheme: a contactless proximity switch comprises an EM mechanism for generating an electromagnetic field, a monitoring circuit for monitoring changes of the electromagnetic field and a processor, wherein the EM mechanism comprises a plurality of different electronic components, the electronic components are respectively communicated with the monitoring circuit, output signals of the monitoring circuit are electrically connected with the processor, and the processor comprises a processing unit for processing the output signals and a control unit for controlling the different electronic components.

By adopting the technical scheme, the EM mechanism generates an electromagnetic field, the measured target is positioned near the electromagnetic field generated by the electronic component, when the change of the displacement of the target causes the change of the disturbance of the electromagnetic field, thereby causing the output signal of the monitoring circuit to change, the processing unit comprehensively judges according to the output signals of different electronic components, confirms the displacement change of the target, finally forms the interaction between the field and the target of the sensing element, instead of the realization of reducing the resistance in the sensing circuit, the proposal of the invention can reduce the magnetic field interference caused by environmental factors, avoid the switch from being incapable of operating, has high repeated positioning precision, good anti-interference performance, high temperature resistance and water resistance, meanwhile, the arrangement of a plurality of electronic components increases the induction distance, can be used in complicated environments such as underwater and the like, can be applied to the fields such as steel, traffic, mines, war industry and the like, and expands the application range of the switch.

The invention further provides that: the temperature compensation circuit is further arranged between the monitoring circuit and the EM mechanism and comprises a temperature coefficient oscillator and a frequency adjustment assembly, the temperature coefficient oscillator is electrically connected with the processor, the frequency adjustment assembly is electrically connected with the EM mechanism, the processor comprises a storage unit, and the processing unit receives the output frequency of the temperature coefficient oscillator and compares the output frequency with temperature data stored in the storage unit and corresponding to the output frequency, so that the temperature difference coefficient is obtained.

By adopting the technical scheme, a specific relation exists between the oscillation frequency and the temperature of the temperature coefficient oscillator, namely different temperatures correspond to different oscillation frequencies. The output frequency of the oscillator is measured, so that a temperature value can be measured, the processing unit receives the output frequency of the temperature coefficient oscillator and compares the output frequency with temperature data stored in the storage unit and corresponding to the output frequency to obtain the temperature value, so that a temperature difference coefficient is obtained, accurate calibration is achieved, the influence of temperature on the Q value of the oscillating circuit is reduced, and the precision and the detection distance of the switch are ensured.

The invention further provides that: the electronic components comprise a response component with a 3D structure and any 2 or more than 2 of an inductor, a transformer, a capacitor and a resistor, and the electronic components are arranged in parallel.

By adopting the technical scheme, the technical scheme of the invention is different from the induction type proximity switch in the prior art in that: according to the electromagnetic disturbance principle, the electromagnetic electronic component with a plurality of frequencies is used for enhancing the electromagnetic field at a farther distance from the sensor surface, so that the induction distance is remarkably increased, the accurate grasping of the displacement distance of the object is obtained according to the magnetic field change with different frequencies, and the accuracy of the proximity switch is improved.

The invention further provides that: the frequency adjusting component comprises a plurality of control switches, and the control switches are respectively connected with different electronic components in series.

By adopting the above technical solution, each electronic component and the switch form the relevant elements of the control frequency adjustment component. For example the capacitor and switch 1 are created by a controller with a frequency determined according to their values, if instead an inductor and switch 2 are used, the inductor having a different capacitance value than the capacitor, a different oscillation frequency will be achieved. Furthermore, if both capacitors and inductors are used, as well as switches 1 and 2, a still further oscillation frequency will be achieved. Of course, these arrangements, combinations and selections of capacitors and switches can also be extended to N capacitor and switch combinations, and assuming 3 operating frequencies, 3 proximity measurements are made sequentially at these 3 different frequencies, and the controller measures each frequency and the corresponding frequency shift due to the proximity of the target and determines the same or similar frequency, and when the values of frequency 2 and frequency 3 are the same or similar, the controller discards the value of frequency 1.

The invention further provides that: the response subassembly with 3D structure includes base plate, base and spiral coil, the base is the round platform setting, be provided with the electrically conductive groove that is the spiral shape that rises on the base, the base is including being two bases of opposite setting, the spiral coil sets up and makes the spiral coil of two bases establish ties mutually along the electrically conductive groove winding of base.

Through adopting above-mentioned technical scheme, spiral coil adopts 3D to pile up the series connection, has improved proximity switch greatly at sensitivity or induction distance's performance, adopts the base mode, makes things convenient for spiral coil quick, accurate winding for it is more convenient to install.

The invention further provides that: the base plate is the setting of L type, base and the vertical setting of base plate diapire.

By adopting the technical scheme, the size of the response assembly is reduced, and the response assembly is used for setting the micro proximity switch.

The invention further provides that: the base is arranged in parallel with the substrate.

By adopting the technical scheme, the proximity switch can be used for a conventional proximity switch, and the performances such as precision, sensitivity or induction distance are greatly increased.

The invention further provides that: the conductive grooves of the two bases are spirally arranged in the same direction.

By adopting the technical scheme, the sensitivity of the technical scheme is 1.5-3 times that of the conventional inductive proximity switch, the response time is shortened, and the accuracy is improved.

The invention further provides that: the conductive grooves of the two bases are spirally arranged in opposite directions.

By adopting the technical scheme, the traces are gathered together, more current is concentrated in the area through the self-resonance mode, and the induction distance of the whole EM field is increased through the basic focusing field, wherein the induction distance of the technical scheme of the invention is 2-4 times of that of the existing induction type proximity switch.

The invention further provides that: the line width of the spiral coil is 0.1mm, the space between the coil turns is 0.25mm, and the thickness of the substrate is 0.5 mm.

By adopting the technical scheme, the repeated positioning method has high repeated positioning precision and good anti-interference performance, can be used in complex environments such as underwater and the like, can be applied to the fields of steel, traffic, mines, war industry and the like, and can enlarge the application range of the switch.

The following describes embodiments of the present invention with reference to the drawings and examples.

Drawings

FIG. 1 is a circuit schematic of an embodiment of the present invention;

fig. 2 is a front view of a response assembly having a 3D structure of embodiment 1 of the present invention;

FIG. 3 is a plan view of a responsive assembly having a 3D structure according to embodiment 2 of the present invention;

FIG. 4 is a schematic structural diagram of an embodiment of the present invention;

FIG. 5 is a flowchart of the operation of an embodiment of the present invention;

FIG. 6 is a table comparing parameters of an embodiment of the present invention and a conventional inductive proximity switch;

reference numerals: the device comprises an EM mechanism 1, an EM mechanism 11, an electronic component 2, a processor 3, a temperature coefficient oscillator 4, a frequency adjusting component 5, a substrate 6, a base 7, a spiral coil 8, a power supply 9 and a target.

Detailed Description

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment as necessary without inventive contribution to the present embodiment after reading the present specification, but all are protected by patent law within the scope of the claims of the present invention.

Referring to fig. 1-6, the present embodiment discloses a contactless proximity switch, which includes an EM mechanism 1 for generating an electromagnetic field, a monitoring circuit for monitoring changes in the electromagnetic field, and a processor 2, wherein the EM mechanism 1 includes a plurality of different electronic components 11, the electronic components 11 are respectively communicated with the monitoring circuit, output signals of the monitoring circuit are electrically connected with the processor 2, and the processor 2 includes a processing unit for processing the plurality of output signals and a control unit for controlling the different electronic components 11.

The embodiment further provides that: the temperature compensation circuit is further arranged between the monitoring circuit and the EM mechanism 1 and comprises a temperature coefficient oscillator 3 and a frequency adjustment component 4, the temperature coefficient oscillator 3 is electrically connected with the processor 2, the frequency adjustment component 4 is electrically connected with the EM mechanism 1, the processor 2 comprises a storage unit, and the processing unit receives the output frequency of the temperature coefficient oscillator 3 and compares the output frequency with temperature data corresponding to the storage unit and the output frequency to obtain a temperature difference coefficient.

The embodiment further provides that: the electronic components 11 comprise response components with 3D structures and any 2 or more than 2 of inductors, transformers, capacitors and resistors, and the electronic components 11 are arranged in parallel.

The embodiment further provides that: the frequency adjustment component 4 includes a plurality of control switches, and the control switches are respectively connected in series with different electronic components 11.

The embodiment further provides that: response subassembly with 3D structure includes base plate 5, base 6 and helical coil 7, base 6 is the round platform setting, be provided with the electrically conductive groove that is the spiral shape that rises on base 6, base 6 is including two bases 6 that are opposite settings, helical coil 7 sets up and makes two bases 6's helical coil 7 establish ties mutually along the electrically conductive groove winding of base 6.

The embodiment further provides that: the base plate 5 is L-shaped, and the base 6 and the bottom wall of the base plate 5 are vertically arranged.

The embodiment further provides that: the susceptor 6 is arranged parallel to the substrate 5.

The embodiment further provides that: the conductive grooves of the two bases 6 are spirally arranged in the same direction.

The embodiment further provides that: the conductive grooves of the two bases 6 are spirally arranged in opposite directions.

The embodiment further provides that: the line width of the spiral coil 7 is 0.1mm, the distance between coil turns is 0.25mm, and the thickness of the substrate 5 is 0.5 mm.

The above-mentioned "between" does not only mean between the orientation and the position, but also means between the interaction of the different parts, and the above-mentioned "upper and lower" are described relatively to each other for the convenience of description and understanding, without excluding the use of other possibilities.

Although the terms EM mechanism 1, electronics assembly 11, processor 2, temperature coefficient oscillator 3, frequency adjustment assembly 4, substrate 5, susceptor 6, helical coil 7, etc. are used more herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

Claims

1. A contactless proximity switch, characterized by: the electromagnetic field monitoring device comprises an EM mechanism for generating an electromagnetic field, a monitoring circuit for monitoring changes of the electromagnetic field and a processor, wherein the EM mechanism comprises a plurality of different electronic components, the electronic components are respectively communicated with the monitoring circuit, output signals of the monitoring circuit are electrically connected with the processor, and the processor comprises a processing unit for processing the output signals and a control unit for controlling the different electronic components.

2. A contactless proximity switch according to claim 1, characterized in that: the temperature compensation circuit is further arranged between the monitoring circuit and the EM mechanism and comprises a temperature coefficient oscillator and a frequency adjustment assembly, the temperature coefficient oscillator is electrically connected with the processor, the frequency adjustment assembly is electrically connected with the EM mechanism, the processor comprises a storage unit, and the processing unit receives the output frequency of the temperature coefficient oscillator and compares the output frequency with temperature data stored in the storage unit and corresponding to the output frequency, so that the temperature difference coefficient is obtained.

3. A contactless proximity switch according to claim 2, characterized in that: the electronic components comprise a response component with a 3D structure and any 2 or more than 2 of an inductor, a transformer, a capacitor and a resistor, and the electronic components are arranged in parallel.

4. A contactless proximity switch according to claim 3, characterized in that: the frequency adjusting component comprises a plurality of control switches, and the control switches are respectively connected with different electronic components in series.

5. A contactless proximity switch according to claim 3, characterized in that: the response subassembly with 3D structure includes base plate, base and spiral coil, the base is the round platform setting, be provided with the electrically conductive groove that is the spiral shape that rises on the base, the base is including two bases that are opposite setting, spiral coil sets up and makes the spiral coil of two bases establish ties mutually along the electrically conductive groove winding of base.

6. A contactless proximity switch according to claim 5, characterized in that: the base plate is the setting of L type, base and the vertical setting of base plate diapire.

7. A contactless proximity switch according to claim 5, characterized in that: the base is arranged in parallel with the substrate.

8. A contactless proximity switch according to claim 5, characterized in that: the conductive grooves of the two bases are spirally arranged in the same direction.

9. A contactless proximity switch according to claim 5, characterized in that: the conductive grooves of the two bases are spirally arranged in opposite directions.

10. A contactless proximity switch according to claim 5, characterized in that: the line width of the spiral coil is 0.1mm, the space between the coil turns is 0.25mm, and the thickness of the substrate is 0.5 mm.