CN218279651U

CN218279651U - Novel electrode structure for collecting electroencephalogram signals

Info

Publication number: CN218279651U
Application number: CN202221718263.2U
Authority: CN
Inventors: 张晋畅; 邢立化; 黄涌
Original assignee: Deep Exploration Beijing Technology Co ltd
Current assignee: Deep Exploration Beijing Technology Co ltd
Priority date: 2022-07-04
Filing date: 2022-07-04
Publication date: 2023-01-13
Anticipated expiration: 2032-07-04

Abstract

The utility model discloses a novel electrode structure for collecting electroencephalogram signals, which comprises an installation shell connected with an electroencephalogram cap, wherein a second PCB which moves along the axial direction of a cavity and rotates relative to the installation shell is arranged in the hollow cavity of the installation shell; an elastic element for driving the second PCB to reset is arranged in the cavity; the second PCB is provided with an inner ring electrode which is in close contact with the second PCB, and pins are uniformly distributed on the bottom of the mounting shell and the surface of the part of the inner ring electrode extending out of the bottom of the mounting shell and used for collecting electroencephalogram signals and transmitting the electroencephalogram signals to the second PCB for processing. The utility model can adjust the position of the pin through the movable and rotatable second PCB board, and is convenient to use; the elastic element can enable the pin to be automatically adjusted according to the shape of the contact surface, can automatically adapt to the shape of the scalp in the using process, is simple in structure, convenient to operate and good in stability, can reduce the interference of an environmental electromagnetic field to signals, and improves the signal-to-noise ratio and the stability.

Description

Novel electrode structure for collecting electroencephalogram signals

Technical Field

The utility model belongs to the technical field of bioelectricity sensor's technique and specifically relates to a novel electrode structure of EEG signal collection is related to.

Background

Electroencephalogram (EEG) is a common bioelectrical signal, and measures changes in brain electrical signals using nerve potential characteristics of brain activity to obtain brain function information, which has an advantage of high time resolution. EEG can be mainly classified into invasive EEG and non-invasive EEG. Invasive EEG has high spatial resolution, but is damaged to the test subject and is difficult to put into practical use. Therefore, non-invasive EEG is currently most widely used.

A silver/silver chloride (Ag/AgCl) electrode (a type of dry electrode) is a common non-invasive EEG reference electrode, and has the advantages of constant electrode potential, difficulty in polarization, low impedance, large exchange current density, and the like. Because it can accurately detect bioelectric signals, it has been widely used in electroencephalogram, electrocardio, and biochemical analysis dry plate bioelectric signal recording electrodes in medical treatment.

Although the dry electrode can stretch into the hair and directly contact with the scalp, the dry electrode usually adopts the harder material of texture, can produce comparatively strong oppression sense to the head, leads to user experience to descend, and because different users' head circumference is different, the position of electroencephalogram signal collection device need be adjusted dry electrode before using, and it is inconvenient to use. Meanwhile, in order to reduce the interference of the environmental electromagnetic field to the signal and improve the signal-to-noise ratio and stability, the acquisition circuit and the structure need to be optimally designed.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a novel electrode structure that EEG signal gathered, the position of electrode can be adjusted, can improve the contact of electrode and user scalp, reduces electrode contact impedance and noise, improves SNR and sensitivity.

The application provides a novel electrode structure for collecting electroencephalogram signals, which comprises an installation shell connected with an electroencephalogram cap in an installation mode, wherein the installation shell is provided with a hollow cavity, and a second PCB which moves along the axial direction of the cavity and rotates relative to the installation shell is arranged in the cavity; an elastic element for driving the second PCB to reset is arranged in the cavity; the second PCB is provided with an inner ring electrode which is in close contact with the second PCB, and pins are uniformly distributed on the bottom of the mounting shell and the surface of the part of the inner ring electrode extending out of the bottom of the mounting shell and used for collecting electroencephalogram signals and transmitting the electroencephalogram signals to the second PCB for processing.

By last, the utility model discloses during the use, through portable and pivoted second PCB board for the position of the pin of inner circle electrode can be adjusted, and it is convenient to use, and the rotation angle's of second PCB board the scope can be set for by people, utilizes limit structure to restrict. The elastic element can enable the pin to be automatically adjusted according to the shape of the contact surface, can automatically adapt to the shape of the scalp in the using process, and has the advantages of simple structure, convenience in operation and good stability. Meanwhile, the acquisition circuit and the structure are optimally designed, so that the interference of an environmental electromagnetic field to signals is reduced, and the signal-to-noise ratio and the stability are improved. The inner ring electrode has the characteristics related to a physiological electric sensor, such as ultra-low impedance, and is specially used for collecting electroencephalogram signals.

Optionally, a first PCB is detachably mounted on the top of the mounting housing, and the first PCB is embedded in a counter bore at the top of the mounting housing.

By last, back in the counter bore is installed to first PCB board, fixes first PCB board on the installation shell via the mode that the screw passes through threaded connection, and connected mode is simple swift, can realize the firm connection of first PCB board and installation shell through simple connection structure, is favorable to simplifying the utility model discloses an electrode structure's dismouting process can also ensure fastening effect simultaneously.

Optionally, the elastic element is a common spring or a wave spring, one end of the elastic element abuts against the first PCB, the other end of the elastic element abuts against the second PCB, and the elastic element and the two PCBs are in insulating contact.

Therefore, the inner ring electrode can have proper tightness according to actual conditions, and the using effect of the electrode structure is improved to a certain extent; the elastic element is not conducted with the two PCB boards.

Optionally, a flange structure protruding into the cavity is arranged at the middle position of the inner ring electrode, a buckle is arranged on the outer peripheral surface of the flange structure, and the second PCB is clamped on the outer peripheral surface of the flange structure through an installation hole in the second PCB by interference fit or the buckle structure.

By last, adopt simple buckle structure can realize that the installation of second PCB board and inner circle electrode is fixed, do benefit to the dismouting process of simplifying electrode structure, make things convenient for connection and separation between the two, make whole electrode structure's easy operation.

Further, the flange structure is internally provided with an inner hexagonal blind hole for inserting an inner hexagonal wrench to rotate the second PCB and the inner ring electrode.

Therefore, the second PCB and the inner ring electrode are rotated through the inner hexagonal blind hole of the inner ring electrode, so that the contact between the pin of the inner ring electrode and the scalp of a user is adjusted and improved, and the contact impedance and noise of the electrode are reduced.

Further, the center of the first PCB board is provided with an inner hexagonal through hole for allowing the inner hexagonal wrench to pass through.

By last, via the interior hexagonal through-hole on the first PCB board, make things convenient for operating tool such as interior hexagonal spanner to stretch into inside the inner ring electrode of electrode structure and rotate, the interior hexagonal through-hole of first PCB constitutes the interference to hexagonal spanner, the corner range of restriction spanner.

Optionally, the shape of the pin end includes, but is not limited to, spherical, needle-like, or planar.

By above, adopt the pin of different shapes, ensure that the pin is stable contact and make the user feel comfortable with user's scalp, make the contact of pin front end and scalp more abundant when guaranteeing the comfort level.

Optionally, the outer surface and the inner wall surface of the mounting shell are coated with a mesh-shaped conductive coating, so as to form a faraday cage for the brain electrode and shield the interference of an environmental electromagnetic field to the brain electrical acquisition signal.

Conductive coatings are coated on the outer surface and the inner wall surface of the installation shell, so that the installation shell and the first PCB form a loop and form a Faraday cage for shielding an environmental electromagnetic field. The conductive coating on the surface of the shell is not conducted with the electrode signal acquisition loop.

Optionally, the conductive material of the electrode structure of the present invention includes, but is not limited to, silver chloride or silver simple substance, the silver chloride or silver simple substance plating layer is coated on the outer surface of the electrode structure, and the thickness of the coating layer is 0.01 to 100 μm.

Optionally, the lower surface of the second PCB is provided with a bonding pad for being compatible with the existing brain electrode product on the market.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings required for the embodiment or the prior art description will be briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts.

Fig. 1 is a schematic structural diagram of the novel electrode structure for electroencephalogram signal acquisition of the present invention;

fig. 2 is a circuit diagram of a second PCB board according to the present invention, which is a first embodiment;

fig. 3 is a circuit diagram of a second PCB board according to the present invention, which is a second embodiment;

fig. 4 is a circuit diagram of a second PCB board according to a third embodiment of the present invention;

fig. 5 is a circuit diagram of a second PCB of the present invention, which is a fourth embodiment;

fig. 6 is a schematic structural diagram of the allen key of the present invention.

The PCB comprises a PCB body, a first PCB board and a second PCB board, wherein 1, the first PCB board is provided; 2. installing a shell; 3. an inner ring electrode; 4. an operational amplifier; 5. an elastic element; 6. and a second PCB board.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1 to 6, the novel electrode structure for electroencephalogram signal collection of the application comprises an installation shell 2, the installation shell 2 is provided with a hollow cavity, an elastic element 5 which moves along the axial direction of the cavity and drives a movable second PCB 6 and a movable second PCB to reset relative to the installation shell 2 is arranged in the cavity, an inner ring electrode 3 is arranged on the second PCB 6, the inner ring electrode 3 is a good conductor with ultra-low impedance and is in close contact with the second PCB 6 to form a circuit path with the second PCB 6. And pins on the inner ring electrodes 3 are formed by injection molding of a conductive material or are coated with a conductive layer on the outer surface, and are in contact with a tin plate of the second PCB 6 to form a passage. The side wall of the mounting shell 2 is provided with four through holes, and every two opposite through holes are symmetrically arranged and used for being mounted and connected with the electroencephalogram cap and leading out an electroencephalogram lead wire. The brain electricity lead wire has certain shielding effect on the interference of the environment electromagnetic field.

The middle position of the inner ring electrode 3 is provided with a flange structure protruding into the cavity of the mounting shell 2, the peripheral surface of the flange structure is provided with a buckle, the center of the second PCB 6 is provided with a mounting hole, and the second PCB 6 is clamped on the peripheral surface of the flange structure through the mounting hole by interference fit or the buckle structure. The typical mounting manner of the mounting hole of the second PCB 6 and the inner ring electrode 3 is a plastic clip, so as to mount and fix the second PCB 6 on the inner ring electrode 3. It is understood that the inner ring electrode 3 can be mounted on the second PCB 6 by other fixing methods, which are not described herein.

First PCB board 1 is installed to the top detachably of installation shell 2, and first PCB board 1 is inlayed in the counter bore of installation shell 2, and the outer edge of first PCB board 1 has the aperture of equipartition, can install in installation shell 2 through self tapping screw. The first PCB 1 and the mounting housing 2 are typically mounted by a self-tapping screw, or can be fixed to the mounting housing 2 by a plug connection, a snap connection, or a paste connection. The first PCB board 1 comprises a passive closed loop and does not comprise electronic components, the inner wall surface and the outer surface of the installation shell 2 are coated with a mesh-shaped conductive coating, the components of the conductive coating include but are not limited to silver simple substance or silver chloride, the conductive coating and the first PCB board 1 form a loop and form a Faraday cage for shielding an environmental electromagnetic field, and the first PCB board 1 also has the function of limiting the elastic component 5.

The elastic element 5 is a common spring, one of two opposite ends of the spring abuts against the first PCB 1, and the other end abuts against the second PCB 6. The elastic element 5 is in insulated contact with the two PCB boards. The elastic element 5 may be a compression spring, a wave spring or other elastic element.

Pins are uniformly distributed on the bottom of the mounting shell 2 and the surface of the part of the inner ring electrode 3 extending out of the bottom of the mounting shell 2, and the resistivity and the surface impedance of the pins are small enough to be used for collecting electroencephalogram signals and transmitting the electroencephalogram signals to the second PCB 6 for processing. The second PCB 6 is provided with a signal acquisition circuit and necessary electrical components, comprises an operational amplifier 4, a resistor, a capacitor and the like, and has functions of an electroencephalogram signal acquisition module, a frequency domain signal conversion module, a quantization index determination module, signal digital-to-analog conversion and amplification processing, filtering, noise reduction, artifact elimination and the like, and signals output by the second PCB 6 have main characteristics of interference resistance, high signal-to-noise ratio, nonlinearity and the like, so that the signal-to-noise ratio and the sensitivity can be improved. The pins are contacted with the scalp, and the acquired electroencephalogram signals are processed by the second PCB 6 and then are accessed to the electroencephalogram acquisition and processing system through electroencephalogram lead wires led out from the circuit of the second PCB. The lower surface of the second PCB 6 is provided with a bonding pad for being compatible with the existing brain electrode product on the market.

The flange structure of the inner ring electrode 3 has an inner hexagonal blind hole inside for an inner hexagonal wrench to insert to rotate the second PCB 6 and the inner ring electrode 3. A second-level stepped hole can be formed in the center of the inner portion of the flange structure, the first level is an inner hexagonal hole, and the second level is a metric threaded blind hole. The center of the first PCB board 1 is provided with an inner hexagonal through hole, an inner hexagonal wrench is allowed to pass through the inner hexagonal through hole, the second PCB board 6 and the inner ring electrode 3 are rotated by means of the inner hexagonal blind hole of the inner ring electrode 3, contact between the electrode and the scalp of a user is adjusted and improved, contact impedance and noise of the electrode are reduced, and the inner hexagonal blind hole can be used for adjusting the position limitation of the tool in the using process. The hexagon socket head cap hole of first PCB board 1 is bigger than the hexagon socket head cap blind hole of inner circle electrode 3 to the hexagon socket head cap model is adjacent, and the purpose is that the hexagon socket head cap hole of first PCB board 1 interferes hexagon socket head cap spanner when using and revolves, thereby restricts the gyration angle of spanner.

The pins for mounting the housing 2 and the inner ring electrode 3 may be made of low-resistivity metal, flexible conductive silica gel, or a polymer material with a silver chloride coating on the outer surface. When collecting the brain electrical signal, because the density of user's hair, length differ, the length of the pin of inner circle electrode 3, hardness, diameter, material isoparametric can set up according to the user demand to choose for use according to user's actual conditions, the one end that second PCB board 6 was kept away from to the pin on inner circle electrode 3 and the installation shell 2 can set up to multiple shapes such as globular (cambered surface form), acicular or plane, ensures that the pin is with user's scalp stable contact and make the user feel comfortable can.

The conductive material of the electrode structure of the present invention includes but is not limited to silver chloride or silver simple substance, and the outer surface of the electrode structure is coated with silver chloride or silver simple substance coating, and the thickness of the coating layer is 0.01-100 μm.

In the present invention, the inner ring electrode 3 is replaceable. The mounting hole in the center of the second PCB may accommodate other styles of electrodes including but not limited to silver chloride electrodes, but the adapted electrodes should have similar mounting structures.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel electrode structure for collecting electroencephalogram signals comprises an installation shell which is connected with an electroencephalogram cap in an installation mode, and is characterized in that the installation shell is provided with a hollow cavity, and a second PCB which moves along the axial direction of the cavity and rotates relative to the installation shell is arranged in the cavity;

an elastic element for driving the second PCB to reset is arranged in the cavity;

the second PCB is provided with an inner ring electrode which is in close contact with the second PCB, and pins are uniformly distributed on the bottom of the mounting shell and the surface of the part of the inner ring electrode extending out of the bottom of the mounting shell and used for collecting electroencephalogram signals and transmitting the electroencephalogram signals to the second PCB for processing.

2. The novel electrode structure for collecting electroencephalogram signals according to claim 1, wherein a first PCB (printed circuit board) is detachably mounted at the top of the mounting shell, and the first PCB is embedded in a counter bore at the top of the mounting shell.

3. The novel electrode structure for collecting electroencephalogram signals according to claim 2, wherein the elastic element is a common spring or a wave spring, one end of the elastic element abuts against the first PCB, the other end of the elastic element abuts against the second PCB, and the elastic element and the two PCBs are in insulated contact.

4. The novel electrode structure for collecting electroencephalogram signals according to claim 2, wherein a flange structure protruding into the cavity is arranged in the middle of the inner ring electrode, a buckle is arranged on the outer peripheral surface of the flange structure, and the second PCB is clamped on the outer peripheral surface of the flange structure through an installation hole in the second PCB in an interference fit mode or a buckle structure.

5. The novel electrode structure for collecting electroencephalogram signals according to claim 4, wherein the flange structure is internally provided with an inner hexagonal blind hole for inserting an inner hexagonal wrench to rotate the second PCB and the inner ring electrode.

6. The novel electrode structure for brain electrical signal collection according to claim 5, wherein the center of the first PCB board has a hexagon socket head cap through hole for allowing the hexagon socket head cap wrench to pass through.

7. The novel electrode structure for brain electrical signal acquisition of claim 1, wherein the shape of the pin end includes but is not limited to spherical, needle-like or planar.

8. The novel electrode structure for electroencephalogram signal acquisition according to claim 1, wherein the outer surface and the inner wall surface of the mounting shell are coated with a mesh-shaped conductive coating for forming a Faraday cage for electroencephalograms and shielding interference of environmental electromagnetic fields on electroencephalogram acquisition signals.

9. The novel electrode structure for collecting electroencephalogram signals according to claim 1, wherein the conductive material of the electrode structure comprises but is not limited to silver chloride or silver simple substance, the outer surface of the electrode structure is coated with a silver chloride or silver simple substance coating layer, and the thickness of the coating layer is 0.01-100 μm.

10. The novel electrode structure for electroencephalogram signal acquisition according to claim 1, wherein a bonding pad is arranged on the lower surface of the second PCB board so as to be compatible with the existing electroencephalogram products on the market.