Electrostatic protection circuit of table tennis serving machine

Abstract

The utility model discloses an electrostatic protection circuit of a table tennis serving machine, which belongs to the technical field of circuit boards of table tennis serving machines, and comprises an IC (integrated circuit) board, an electrostatic protection mechanism, a connecting terminal J and a reflective infrared photoelectric sensor for counting table tennis balls which are sequentially connected in series, when static charges accumulated in the friction process of a roller of the table tennis serving machine and a table tennis ball act on the IC circuit board through the reflection type infrared photoelectric sensor, the ESD diode D1 instantly discharges the static charges to the GND grounding end, and if an equivalent protection resistor R is not arranged in the static protection mechanism at the moment, the static charges are discharged to the GND grounding end. At the moment, the discharge current cannot be limited due to small resistance in a discharge loop of the electrostatic protection mechanism, large current is instantly generated to act on the IC circuit board, and then the IC circuit board is seriously damaged, so that surge current is limited through an equivalent protection resistor R which is connected in series, ground wire rebound is reduced, and finally the IC circuit board is prevented from being damaged by static electricity.

Description

Technical Field

[0001] The utility model relates to the technical field of table tennis serving machine circuit boards, and more specifically to an electrostatic protection circuit for a table tennis serving machine. Background Art

[0002] When the table tennis serving machine is in operation, the static charge accumulated during the friction between the roller and the table tennis ball can generate static electricity of up to several thousand volts. This is especially true when the table tennis serving machine is used in a low temperature and dry environment, as static electricity is more likely to be generated.

[0003] In the prior art, a table tennis serving machine is composed of a reflective infrared photoelectric sensor for detecting table tennis ball counts, a table tennis serving machine IC circuit board, and wires. The reflective infrared photoelectric sensor for detecting table tennis ball counts is connected to the table tennis serving machine IC circuit board through a relatively long wire. The relatively long wire input will have a relatively large distributed capacitance and distributed inductance, and static electricity is released in a short time in the form of a relatively large current, which eventually causes damage to the table tennis serving machine IC circuit board connected to the photoelectric sensor. Utility Model Content

[0004] 1. Technical issues to be solved

[0005] In view of the problems existing in the prior art, the utility model aims to provide an electrostatic protection circuit for a table tennis serving machine, thereby solving the technical problem of an IC circuit board (100) being damaged by static electricity.

[0006] 2. Technical solution

[0007] In order to solve the above problems, the utility model adopts the following technical solutions:

[0008] An electrostatic protection circuit for a table tennis serving machine, comprising:

[0009] IC circuit board; and

[0010] Reflective infrared photoelectric sensor, which is used to count table tennis balls;

[0011] It also includes:

[0012] an electrostatic protection mechanism, the input end of which is connected to the output end of the IC circuit board to achieve electrostatic protection; and

[0013] The connection terminal J is connected in series between the output end of the electrostatic protection mechanism and the input end of the reflective infrared photoelectric sensor to achieve connection.

[0014] As a preferred solution of the utility model, the electrostatic protection mechanism at least includes:

[0015] An ESD diode D1, one end of which is connected to pin 1 of the IC circuit board, and the other end of which is connected to the GND ground terminal, and is used to discharge static charge to the GND ground terminal; and

[0016] The equivalent protection resistor R is connected in series between the 1 pin of the IC circuit board and the input end of the connection terminal J, and is connected in parallel with the ESD diode D1, so as to limit the surge current and reduce the ground bounce.

[0017] As a preferred solution of the present invention, the connection terminal J has at least three parallel connection ends, which are connection end A, connection end B and connection end C in sequence.

[0018] As a preferred solution of the utility model, the equivalent protection resistor R includes a resistor R1, a resistor R2 and a resistor R3, one end of the resistor R2 and the resistor R3 are both connected to pin 1 of the IC circuit board, the resistor R2 and the resistor R3 are connected in parallel, the other end of the resistor R2 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the input end of the reflective infrared photoelectric sensor through the A connection end, the other end of the resistor R3 is connected to the input end of the reflective infrared photoelectric sensor through the B connection end, and the C connection end is connected to the GND grounding end.

[0019] As a preferred solution of the utility model, the electrostatic protection mechanism further includes:

[0020] The capacitor C1 has one end connected to pin 1 of the IC circuit board and the other end connected to the GND ground terminal. The capacitor C1 is connected in parallel with the ESD diode D1 to stabilize the input voltage.

[0021] As a preferred solution of the utility model, pin 7 of the IC circuit board is connected to the GND ground terminal.

[0022] As a preferred solution of the utility model, it also includes:

[0023] A 5V voltage terminal, whose output terminal is connected to pin 14 of the IC circuit board;

[0024] The capacitor C2 has one end connected to the 5V voltage output terminal, and the other end connected to the GND ground terminal.

[0025] 3. Beneficial effects

[0026] Compared with the prior art, the advantages of the present invention are:

[0027] (1) In the present invention, when the static charge accumulated by the roller and the table tennis ball during the friction process of the table tennis serving machine acts on the IC circuit board through the reflective infrared photoelectric sensor, the ESD diode D1 will instantly discharge the static charge to the GND ground terminal. If the equivalent protection resistor R is not set in the electrostatic protection mechanism at this time, the discharge current in the discharge circuit of the electrostatic protection mechanism will be unable to be limited due to the small resistance, and a large current will be instantly generated to act on the IC circuit board, which will then cause serious damage to the IC circuit board. Therefore, the equivalent protection resistor R connected in series is used to limit the surge current and reduce the ground wire rebound, thereby ultimately preventing the IC circuit board from being damaged by static electricity;

[0028] (2) The capacitor C1 in the present invention can stabilize the input voltage. The equivalent protection resistor R and the capacitor C1 form an RC circuit, which can effectively filter and maintain the integrity of the signal. When static electricity or other interfering signals are introduced, the RC circuit can effectively absorb them, further improving the electrostatic protection capability of the electrostatic protection mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the circuit principle diagram of the utility model;

[0030] Description of the numbers in the figure:

[0031] 100. IC circuit board;

[0032] 200, electrostatic protection mechanism; 210, equivalent protection resistor R;

[0033] 300, connecting terminal J;

[0034] 400, reflective infrared photoelectric sensor; DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the utility model in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0036] Embodiment 1:

[0037] See also Figure 1 , a table tennis serving machine electrostatic protection circuit, which is composed of an IC circuit board 100, an electrostatic protection mechanism 200, a connection terminal J 300 and a reflective infrared photoelectric sensor 400 for counting table tennis balls, which are sequentially connected in series, and is specifically described as follows:

[0038] The IC circuit board 100 has 14 pins, such as Figure 1 In the state shown, there are 7 pins on the left and right sides, the 7th pin of the IC circuit board 100 is connected to the GND ground terminal, the 14th pin is externally connected to the 5V voltage terminal, the above-mentioned 5V voltage output terminal is also externally connected to a capacitor C2 for stabilizing the output voltage, and the other end of the capacitor C2 is connected to the GND ground terminal;

[0039] The output end of the IC circuit board 100 is connected to the input end of the electrostatic protection mechanism 200 to achieve electrostatic protection. Figure 1 In the state shown, the electrostatic protection mechanism 200 is at least composed of an ESD diode D1 and an equivalent protection resistor R 210, which is described in detail as follows:

[0040] One end of the ESD diode D1 is connected to pin 1 of the IC circuit board 100, and the other end thereof is connected to the GND ground terminal to discharge the static charge to the GND ground terminal;

[0041] The equivalent protection resistor R 210 is connected in series between the 1 pin of the IC circuit board 100 and the input end of the connection terminal J 300 , and is connected in parallel with the ESD diode D1 to limit the surge current, thereby reducing the ground bounce;

[0042] The connection terminal J 300 is connected in series between the output end of the electrostatic protection mechanism 200 and the input end of the reflective infrared photoelectric sensor 400 to achieve connection;

[0043] like Figure 1 In the state shown, the equivalent protection resistor R 210 is composed of a resistor R1, a resistor R2 and a resistor R3, one end of the resistor R2 and the resistor R3 are both connected to pin 1 of the IC circuit board 100, the resistor R2 and the resistor R3 are connected in parallel, the other end of the resistor R2 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the input end of the reflective infrared photoelectric sensor 400 through the A connection end, the other end of the resistor R3 is connected to the input end of the reflective infrared photoelectric sensor 400 through the B connection end, and the C connection end is connected to the GND grounding end;

[0044] When the static charge accumulated by the roller of the table tennis serving machine and the table tennis ball in the friction process acts on the IC circuit board 100 through the reflective infrared photoelectric sensor 400, the ESD diode D1 will instantly discharge the static charge to the GND ground terminal. If the equivalent protection resistor R210 is not set in the electrostatic protection mechanism 200 at this time, the discharge current cannot be limited due to the small resistance in the discharge circuit of the electrostatic protection mechanism 200, and a large current is instantly generated to act on the IC circuit board 100, which then causes serious damage to the IC circuit board 100. Therefore, the equivalent protection resistor R210 connected in series is used to limit the surge current and reduce the ground wire rebound.

[0045] Embodiment 2:

[0046] In order to further improve the electrical protection capability of the utility model, this embodiment is optimized on the basis of the embodiment 1, and a capacitor C1 for stabilizing the input voltage is further provided in the electrostatic protection mechanism 200, as follows:

[0047] One end of the capacitor C1 is connected to pin 1 of the IC circuit board 100, and the other end is connected to the GND ground terminal, and the capacitor C1 is connected in parallel to the ESD diode D1;

[0048] The capacitor C1 can stabilize the input voltage. The equivalent protection resistor R 210 and the capacitor C1 in this embodiment form an RC circuit. The RC circuit can effectively filter and maintain the integrity of the signal. When static electricity or other interference signals are injected, the RC circuit can effectively absorb them, further improving the electrostatic protection capability of the electrostatic protection mechanism 200. The above measures can effectively prevent the technical problem of the IC circuit board 100 being damaged by static electricity.

[0049] The above is only a preferred specific implementation method of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes within the technical scope disclosed by the utility model according to the technical solution and improved ideas of the utility model, which should be included in the protection scope of the utility model.

Claims

1. A table tennis serving machine electrostatic protection circuit, comprising: IC circuit board (100); as well as A reflective infrared photoelectric sensor (400) for counting table tennis balls; It is characterized by: also including: An electrostatic protection mechanism (200), the input end of which is connected to the output end of the IC circuit board (100) to achieve electrostatic protection; and The connection terminal J (300) is connected in series between the output end of the electrostatic protection mechanism (200) and the input end of the reflective infrared photoelectric sensor (400) to achieve connection.

2. The electrostatic protection circuit of a table tennis serving machine according to claim 1, characterized in that: The electrostatic protection mechanism (200) at least comprises: An ESD diode D1, one end of which is connected to pin 1 of the IC circuit board (100), and the other end of which is connected to the GND ground terminal, and is used to discharge static electricity to the GND ground terminal; and An equivalent protection resistor R (210) is connected in series between pin 1 of the IC circuit board (100) and the input end of the connection terminal J (300), and is connected in parallel with the ESD diode D1, and is used to limit surge current and reduce ground bounce.

3. The electrostatic protection circuit of a table tennis serving machine according to claim 2, characterized in that: The connection terminal J (300) has at least three parallel connection ends, which are connection end A, connection end B and connection end C in sequence.

4. The electrostatic protection circuit of a table tennis serving machine according to claim 3, characterized in that: The equivalent protection resistor R (210) comprises a resistor R1, a resistor R2 and a resistor R3, one end of each of the resistors R2 and R3 is connected to pin 1 of the IC circuit board (100), the resistors R2 and R3 are connected in parallel, the other end of the resistor R2 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the input end of the reflective infrared photoelectric sensor (400) via the A connection end, the other end of the resistor R3 is connected to the input end of the reflective infrared photoelectric sensor (400) via the B connection end, and the C connection end is connected to the GND grounding end.

5. An electrostatic protection circuit for a table tennis serving machine according to any one of claims 2 to 4, characterized in that: The electrostatic protection mechanism (200) further comprises: A capacitor C1, one end of which is connected to pin 1 of the IC circuit board (100), and the other end of which is connected to the GND ground terminal. The capacitor C1 is connected in parallel with the ESD diode D1 and is used to stabilize the input voltage.

6. The electrostatic protection circuit of a table tennis serving machine according to claim 1, characterized in that: The 7 pins of the IC circuit board (100) are connected to the GND ground terminal.

7. The electrostatic protection circuit of a table tennis serving machine according to claim 1, characterized in that: Also includes: A 5V voltage terminal, the output end of which is connected to the 14th pin of the IC circuit board (100); The capacitor C2 has one end connected to the 5V voltage output terminal, and the other end connected to the GND ground terminal.

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