CN218634387U

CN218634387U - PCB circuit board and electric tool

Info

Publication number: CN218634387U
Application number: CN202222581171.0U
Authority: CN
Inventors: 施涵钦
Original assignee: Jiangsu Dongcheng Tools Technology Co Ltd
Current assignee: Jiangsu Dongcheng Tools Technology Co Ltd
Priority date: 2022-09-28
Filing date: 2022-09-28
Publication date: 2023-03-14
Anticipated expiration: 2032-09-28

Abstract

The utility model discloses a PCB circuit board, which comprises a substrate provided with electronic components, wherein a plurality of through holes are penetrated through the substrate, the substrate is fixed on an electronic device shell through screws by the through holes, a first bonding pad and a second bonding pad are covered along the upper opening and the circumferential direction of the through holes, a solder mask is covered on the upper surface of the first bonding pad, a plurality of through grooves are penetrated on the solder mask, conductive layers are covered in the through grooves, and the conductive layers are electrically connected with the screws; the second bonding pad is positioned at the periphery of the first bonding pad and is grounded; a plurality of first pointed ends are distributed on the outer side wall of the first bonding pad, and a plurality of second pointed ends are distributed on the inner side wall of the second bonding pad. Therefore, when the first pad and the second pad are subjected to high-voltage discharge through the first tip and the second tip, the high-voltage discharge is effectively released to the ground, and the damage of an electrostatic field and electrostatic current to components on the PCB can be avoided, so that the safety performance of the PCB is improved.

Description

PCB circuit board and electric tool

[ technical field ] A method for producing a semiconductor device

The utility model relates to an electron field especially relates to a PCB circuit board and electric tool.

[ background of the invention ]

A PCB, also known as a printed circuit board or a printed circuit board, is an important electronic component, which is a support for electronic components and is a carrier for electrical interconnection of electronic components.

Electrostatic discharge (ESD) refers to a phenomenon in which two objects having different electrostatic potentials are discharged by breaking down a medium between the two objects after the energy of an electrostatic field reaches a certain degree due to electrostatic charge transfer between the two objects caused by direct contact or electrostatic field induction.

The PCB is easy to be damaged by electrostatic discharge in the processes of production, manufacture, assembly, transportation, use and the like, particularly, the PCB is high in electrostatic sensitivity of integrated circuit components, and the used components tend to be miniaturized due to the miniaturization trend of the existing circuit, the withstand voltage is reduced, the electrostatic impact resistance is weakened, and the electrostatic electric field and the electrostatic current generated by the electrostatic discharge are easy to damage the components on the PCB.

The CN100518439C patent of the present invention discloses a printed circuit board for preventing electrostatic discharge, on which a plurality of electronic components are mounted, the printed circuit board has a plurality of through holes, which are fixed inside an electronic device through the through holes, a first copper foil and a second copper foil are laid around the through holes, the first copper foil and the second copper foil are laid on the same signal layer, the outer edge of the first copper foil has a plurality of tips, the second copper foil extends to the edge of the printed circuit board, the inner edge of the second copper foil also has a plurality of tips, and the first copper foil is insulated from the second copper foil. The scheme does not solve the problems of stability and reliability of electrostatic charge conduction, so that the electrostatic charge is easy to interrupt in the conduction process, and further the PCB is short-circuited to cause the damage of electronic elements.

Therefore, there is a need for a PCB with electrostatic discharge protection to solve the above problems.

[ Utility model ] content

To prior art's not enough, the utility model aims to provide a PCB circuit board, it adopts following technical scheme:

a PCB circuit board comprises a substrate provided with electronic elements, wherein a plurality of through holes penetrate through the substrate, the substrate is fixed on an electronic device shell through screws by the through holes, a first pad and a second pad are circumferentially covered along an upper opening of each through hole, a solder mask covers the upper surface of each first pad, a plurality of through grooves penetrate through the solder mask, conductive layers cover the through grooves, and the conductive layers are electrically connected with the screws;

the second bonding pad is positioned at the periphery of the first bonding pad and is grounded;

the outer side wall of the first bonding pad is distributed with a plurality of first pointed ends, the inner side wall of the second bonding pad is distributed with a plurality of second pointed ends, the first pointed ends point to the inner side wall of the second bonding pad, and the second pointed ends point to the outer side wall of the first bonding pad.

Furthermore, the bottom of the conductive layer is electrically connected to the first pad, and the top of the conductive layer protrudes from the upper surface of the solder mask layer.

Preferably, the conductive layer is a solder paste layer.

Further, the first bonding pad and the second bonding pad are both annular, an annular groove is formed between the first bonding pad and the second bonding pad, and the first tips and the second tips are arranged in the annular groove in a staggered mode.

Further, first pointed end with the second pointed end all is isosceles triangle form, first pointed end equidistant circumference distribution in on the first pad lateral wall, the equidistant circumference distribution of second pointed end in on the second pad medial wall.

Furthermore, the first bonding pad and the second bonding pad, and the first tip and the second tip are made of copper foil.

Further, discharge distances are reserved between the first tip end and the inner side wall of the second bonding pad and between the second tip end and the outer side wall of the first bonding pad.

Preferably, the discharge distance is 0.1mm to 0.3mm.

Further, the solder mask is annular and the solder mask external diameter is less than first pad external diameter, and the internal diameter is more than or equal to first pad internal diameter.

Further, the through grooves are circumferentially distributed in the inner ring portion of the solder mask layer at equal intervals.

The utility model discloses still relate to an electric tool, electric tool includes the PCB circuit board.

Compared with the prior art, the utility model discloses following beneficial effect has:

(one) the utility model discloses a cover the solder mask on first pad, when effectively preventing because of installation or uninstallation screw, twist to move the operation and arouse that the copper foil upwarps or the copper foil breaks away from the problem of base plate and takes place, guarantee the quality of PCB circuit board.

The utility model discloses set up a plurality of logical grooves on the solder mask, and pack the solder paste layer in the logical groove, and the top bulges in the solder mask upper surface, when making the screw tighten with the electronic device casing, guarantee that the screw is connected with the effective electricity of solder paste layer; meanwhile, the solder paste layer is electrically connected with the first bonding pad, so that the stability and reliability of electrostatic charge conduction are ensured.

(III) the utility model discloses first most advanced and second most advanced are the staggered arrangement and arrange in the ring channel, can reduce the distance between first pad and the second pad like this to be favorable to arranging of PCB circuit board, save space resources.

(IV) the utility model discloses the second pad is located first pad periphery and second pad ground connection, like this when first pad and second pad carry out high-voltage discharge through first most advanced and second most advanced, effectively releases to ground, can avoid electrostatic field and electrostatic current to cause the harm to the components and parts on the PCB circuit board to improve PCB circuit board security performance.

[ description of the drawings ]

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings:

fig. 1 is a top view structural diagram of the PCB circuit board of the present invention;

FIG. 2 is a partially enlarged view of the PCB circuit board of the present invention;

FIG. 3 isbase:Sub>A cross-sectional view taken at an angle A-A of the PCB circuit board and the electronic device housing of the present invention;

fig. 4 is a first pad structure view of the present invention;

FIG. 5 is a second pad structure view of the present invention;

fig. 6 is a diagram of a first embodiment of a solder resist layer of the present invention;

fig. 7 is a diagram of a second embodiment of the solder resist layer of the present invention.

Fig. 8 is a second bonding pad structure view of the arc shape of the present invention.

The meaning of the reference symbols in the figures:

1. electronic component 2, substrate 3, through hole 4, screw 5, electronic device shell 6, first pad 7, second pad 8, solder mask 9, through groove 10, conducting layer 11, first tip 12, second tip 13, annular groove 14, arc-shaped groove

[ detailed description ] embodiments

The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Words such as "upper," "top," "bottom," "inner," "outer," and the like, which indicate orientations or positional relationships, are used solely based on the orientations or positional relationships shown in the drawings for ease of description and simplicity of description, but do not indicate or imply that the referenced features must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

Referring to fig. 1 to 3, a PCB circuit board includes a substrate 2 mounted with an electronic component 1, a plurality of through holes 3 penetrate through the substrate 2, the substrate 2 is fixed on an electronic device housing 5 by the through holes 3 through screws 4, a first pad 6 and a second pad 7 are covered along an upper opening and a circumferential direction of the through holes 3, and a solder resist layer 8 is covered on an upper surface of the first pad 6, so that a problem that a copper foil is warped or separated from the substrate 2 due to a twisting operation when the screws 4 are mounted or dismounted can be effectively prevented, and quality of the PCB circuit board is ensured, wherein the first pad 6 and the second pad 7 are both covered on an upper surface of the substrate 2.

As shown in fig. 1 to fig. 3, a plurality of through slots 9 penetrate through the solder resist layer 8, a conductive layer 10 covers the through slots 9, the top of the conductive layer 10 is electrically connected to the screws 4, and the bottom of the conductive layer 10 is electrically connected to the first pads 6; preferably, the conductive layer 10 is a solder paste layer, and thus the through-groove 9 is filled with the solder paste layer, so that when the screw 4 is screwed with the electronic device casing 5, the screw 4 is ensured to be effectively electrically connected with the solder paste layer; meanwhile, the solder paste layer is electrically connected with the first bonding pad 6, so that the stability and reliability of electrostatic charge transmission are ensured. Wherein, the top of the conductive layer 10 protrudes out of the upper surface of the solder mask layer 8, so that the screw 4 is contacted with the top of the solder paste layer more closely, and the electrostatic charge transmission stability is further improved.

Referring to fig. 3, the second pad 7 is located at the periphery of the first pad 6, and the second pad 7 is grounded, so that when the first pad 6 and the second pad 7 perform high-voltage discharge through the first pointed end 11 and the second pointed end 12, the discharge to the ground is effectively performed, and damage to components on the PCB caused by the electrostatic field and the electrostatic current can be avoided, thereby improving the safety performance of the PCB.

As shown in fig. 3, a plurality of first tips 11 are distributed on the outer sidewall of the first pad 6, a plurality of second tips 12 are distributed on the inner sidewall of the second pad 7, the first tips 11 point to the inner sidewall of the second pad 7, and the second tips 12 point to the outer sidewall of the first pad 6. The first bonding pad 6 and the second bonding pad 7 are both annular, an annular groove 13 is formed between the first bonding pad 6 and the second bonding pad 7, and the first pointed ends 11 and the second pointed ends 12 are arranged in the annular groove 13 in an interlaced manner, so that no matter the static positive charges or the static negative charges exist, the high-voltage discharge can be realized quickly and effectively, and the static discharge protection of the PCB is realized; meanwhile, compared with the tip-to-tip arrangement, the tip staggered arrangement can save the layout space of the PCB and prevent the copper foil from being damaged by electric shock due to high-voltage discharge, and because the two tips are opposite, the discharge voltage is high, and the two tip copper foils are rare and weak and are easy to be damaged by electric shock.

In addition, as shown in fig. 8, the second bonding pad 7 in the embodiment may be arc-shaped, the first bonding pad 6 is ring-shaped, an arc-shaped groove 14 is formed between the first bonding pad and the first bonding pad, and the first pointed ends 11 and the second pointed ends 12 are alternately arranged in the arc-shaped groove 14, so that compared with the annular second bonding pad 7, the space resource occupied by the arc-shaped second bonding pad 7 is smaller, which is more favorable for the layout of the electronic component 1 on the PCB circuit board.

In this embodiment, first most advanced 11 and second most advanced 12 all are isosceles triangle form, and first most advanced 11 equidistant circumference distributes on 6 lateral walls of first pad, and the equidistant circumference of second most advanced 12 distributes on 7 inside walls of second pad, and when the electrostatic voltage of being convenient for like this releases, it is more effective fast, and then improves the reliability of electrostatic charge conduction.

In this embodiment, the first pad 6 and the second pad 7, and the first tip 11 and the second tip 12 are made of copper foil, and have good conductivity.

In this embodiment, the discharging distances are left between the first pointed end 11 and the inner side wall of the second pad 7, and between the second pointed end 12 and the outer side wall of the first pad 6, so that the first pad 6 and the second pad 7 are insulated from each other, and preferably, the discharging distance is 0.1mm to 0.3mm, so that compared with the case that the first pad 6 and the second pad 7 are directly connected, the problem of direct short circuit of a PCB circuit board caused by electrostatic discharge can be effectively avoided.

In the embodiment, the solder mask layer 8 is annular, and the outer diameter of the solder mask layer 8 is smaller than that of the first pad 6, so that the electrostatic discharge effect between the second tip 12 and the first pad 6 is facilitated, and the phenomenon that the electrostatic discharge between the solder mask layer 8 and the first pad is blocked because the coverage area of the solder mask layer is too large is prevented; meanwhile, the inner diameter of the solder mask layer 8 is larger than or equal to that of the first welding pad 6, so that the solder mask layer 8 is ensured not to obstruct the installation of the screw 4.

In this embodiment, the through grooves 9 are circumferentially distributed in the inner ring portion of the solder resist layer 8 at equal intervals, wherein the through grooves 9 may be through-holes that penetrate up and down as shown in fig. 5, or the through grooves 9 may be U-shaped grooves that penetrate up and down as shown in fig. 4, and the openings of the through grooves face the center of the through hole 3; in addition, in the tin cream layer filling process, the bottom of the tin cream layer is in contact with the first welding pad 6, the top of the tin cream layer protrudes out of the solder mask layer 8 and then is in contact with the screw 4, and effectiveness and stability of electrostatic conduction can be guaranteed.

The utility model relates to a point discharge principle, it is very intensive for the point department electric charge of electrified body, and there is stronger electric field near it for remaining a small amount of ion accelerated motion in the air, these high-speed moving's ion striking air molecule makes more molecule ionization, and at this moment the air becomes the conductor, can make the electric charge on the conductor release through the air.

The utility model also relates to an electric tool, which uses the PCB circuit board to effectively avoid the influence of electrostatic discharge on the electronic device, protect the electronic element 1 from electrostatic damage, further prolong the service life of the electronic element 1 and reduce the maintenance rate of the electric tool; the electric tool can be an electric drill, an electric pick, an electric hammer, an electric wrench and the like, the electronic device is generally an MCU controller, and a shell of the MCU controller is generally an aluminum alloy shell.

The utility model discloses a theory of operation does:

a certain amount of electrostatic charges are generally accumulated on the surface of a human body, and when the human body directly or indirectly touches the electronic device shell 5, the electrostatic charges strike the electronic device shell 5, based on the principle of current trend in electrostatic discharge, that is, the current always finds a path with the shortest path and the lowest impedance to be released to the ground, so that the current is conducted to the second pad 7 (grounding point) along the first pad 6 of the PCB, and is finally released to the ground.

In this embodiment, when the electronic device casing 5 contacts static electricity or a static electric field, the static electric charge hitting the electronic device casing 5 is firstly conducted to the solder paste layer through the screw 4, then conducted to the first pad 6 through the solder paste layer, and then discharged through the first tip 11 on the first pad 6 or the second tip 12 on the second pad 7, and after a large amount of electric charges generated by the static discharge are accumulated at the first tip 11 or the second tip 12, the electric charges are rapidly discharged to the ground in a tip discharge manner, so that damage of the static electric field and the static current to the electronic element 1 during the static discharge is avoided.

The present invention is not limited to the above-mentioned embodiments, and those skilled in the art can easily understand that the PCB circuit board of the present invention has many other alternatives without departing from the principle and scope of the present invention, and the protection scope of the present invention is subject to the content of the claims.

Claims

1. The utility model provides a PCB circuit board, is including the base plate of installing electronic component, it has a plurality of through-holes to run through on the base plate, the through-hole passes through the screw will the base plate is fixed in on the electron device casing, its characterized in that: a first pad and a second pad are circumferentially covered along the upper opening of the through hole, a solder mask is covered on the upper surface of the first pad, a plurality of through grooves penetrate through the solder mask, a conductive layer is covered in the through grooves, and the conductive layer is electrically connected with screws;

2. The PCB circuit board of claim 1, wherein: the bottom of the conducting layer is electrically connected to the first bonding pad, the top of the conducting layer protrudes out of the upper surface of the solder mask layer, and the conducting layer is a solder paste layer.

3. The PCB circuit board of claim 1, wherein: the first bonding pad and the second bonding pad are both annular, an annular groove is formed between the first bonding pad and the second bonding pad, and the first tips and the second tips are arranged in the annular groove in an staggered mode.

4. The PCB circuit board of claim 3, wherein: first pointed end with the second pointed end all is isosceles triangle form, first pointed end equidistant circumference distribute in on the first pad lateral wall, second pointed end equidistant circumference distribute in on the second pad inside wall.

5. The PCB circuit board of claim 1 or 3, wherein: the first bonding pad, the second bonding pad, the first tip and the second tip are made of copper foil.

6. The PCB circuit board of claim 1, wherein: and discharge distances are reserved between the first tip end and the inner side wall of the second bonding pad and between the second tip end and the outer side wall of the first bonding pad.

7. The PCB circuit board of claim 6, wherein: the discharge distance is 0.1 mm-0.3 mm.

8. The PCB circuit board of claim 1, wherein: the solder mask is annular and the solder mask external diameter is less than first pad external diameter, and the internal diameter is more than or equal to first pad internal diameter.

9. The PCB circuit board of claim 1, wherein: the through grooves are distributed in the inner ring portion of the solder mask layer in the circumferential direction at equal intervals.

10. An electric power tool characterized in that: the power tool comprising a PCB circuit board according to any of claims 1-9.