阅读说明：本技术 一种具有自动切换信号源的分配板卡 (Distribution board card with automatic switching signal source ) 是由 曾水生 殷耀东 李大杰 林华铨 于 2021-09-07 设计创作，主要内容包括：本发明公开了分配板卡领域的一种具有自动切换信号源的分配板卡,包括固定板体和吹尘单元,控制端口包括两种通讯连接方式用于AV板与中控CPU板的电性连接,中控CPU板还设置有对信号源进行切换的输入信号切换模块,将两种通讯连接方式用于AV板与中控CPU板的电性连接,自动切换遵循后入先出原则,在上电时HDMI1具有最高优先级,当检测高优先级无信号时,自动转为低一优先级信号,当有新的输入信号接入时,则自动切换到新的输入通道,通过该输入信号切换模块方便对HDMI输入和VGA输入的信号进行切换,且能够保证优先级,并确保新信号输入时及时更换到新的输入通道。(The invention discloses a distribution board card with an automatic switching signal source, which belongs to the field of distribution board cards and comprises a fixed board body and a dust blowing unit, wherein a control port comprises two communication connection modes for electrically connecting an AV board and a central control CPU board, the central control CPU board is also provided with an input signal switching module for switching the signal source, the two communication connection modes are used for electrically connecting the AV board and the central control CPU board, the automatic switching follows the principle of last-in first-out, HDMI1 has the highest priority when the power is on, when no signal with high priority is detected, the signal is automatically converted into a signal with low priority, when a new input signal is connected, the signal is automatically switched to a new input channel, the signals input by the HDMI and VGA are conveniently switched by the input signal switching module, the priority can be ensured, and the new signal can be timely replaced to the new input channel.)

1. The utility model provides a distribution integrated circuit board with automatic switch-over signal source, includes fixed plate body (1) and fixed mounting blow dirt unit (2) of fixed plate body (1) up end one end to fixed mounting AV board and central control CPU board, its characterized in that on the up end of fixed plate body (1): the AV board is provided with a video port, an audio port and a control port, and the control port comprises a UART (universal asynchronous receiver/transmitter) and a USB (universal serial bus) communication connection mode and is used for electrically connecting the AV board with the central control CPU (central processing unit) board;

the method comprises the following steps that communication between an AV board and a central control CPU board is carried out through a UART interface, control of the central control CPU board on the AV board and collection of state data of the AV board are achieved, and when the state of a video signal interface changes, a main MCU of the AV board actively reports the state change through a serial port;

the communication between the AV board and the central control CPU board is carried out through the USB interface, the control of the central control CPU board on the AV board and the collection of each state data of the AV board are realized, and when the state of the video signal interface changes, the main MCU of the AV board actively reports the state change through the USB interface;

the central control CPU board comprises an input signal switching module for switching HDMI input signals and VGA input signals and an output signal control module for controlling HDMI output and VGA output, and is also provided with an EDID module for expanding display identification data and a power-off memory module capable of performing power-off protection memory.

2. The distribution board card with the automatic switching signal source according to claim 1, wherein: the video port comprises an HDMI input and a VGA input, a 5V signal of the HDMI acquires the state of an HMDI input channel, whether HDMI signal source equipment is accessed is detected through the 5V signal, a 5 th pin and a 10 th pin of the VGA signal equipment interface are communicated and grounded, and the detection of the physical connection state of user equipment connected with the VGA input interface is realized.

3. The distribution board card with the automatic switching signal source according to claim 2, wherein: the video port comprises HDMI output and VGA output, the HPD signal of the HDMI acquires the state of the HMDI output channel, namely, whether the HDMI display equipment is accessed is detected through the HPD signal, and the 5 th pin and the 10 th pin of the VGA signal equipment interface are communicated and grounded, so that the detection of the physical connection state of the user equipment connected with the VGA output interface is realized.

4. The distribution board card with the automatic switching signal source according to claim 3, wherein: the UART and USB two communication connection modes follow the following two signal communication logics:

1) the input of HDMI audio and video needs to be switched synchronously;

2) when VGA is selected by input, VGA can realize no video signal, only audio signal is still transmitted to 2 output channels 3.5, and 3.5 input audio is not output to HDMI.

5. The distribution board card with the automatic switching signal source according to claim 4, wherein: the input signal switching module supports two modes of instruction switching and automatic switching by setting a switching mode through an instruction;

the automatic switching follows the principle of last-in-first-out:

1) when power is on, the HDMI1 has the highest priority, the priority is sequentially reduced from the HDMI1, the HDMI2, the HDMI3 and the VGA +3.5, and when no signal with high priority is detected, the signal is automatically converted into a signal with a lower priority;

2) when a new input signal is accessed, automatically switching to a new input channel;

3) the automatic switching mode is compatible with manual switching, namely, in the automatic switching mode, instruction switching is supported.

6. The distribution board card with the automatic switching signal source according to claim 5, wherein: the EDID module includes two modes of an automatic mode and a manual mode, wherein the automatic mode follows the following working logic:

1) when the EDID is electrified, learning the EDID of the 1 st HDBT1 port connecting device, automatically storing the EDID in an EDID6, if the EDID is learned to be in a DVI format, automatically converting the EDID into the HDMI, wherein the audio frequency is PCM2.0, and reading the EDID again and covering the EDID data of the last time when the EDID is electrified;

2) if the HDBT is not connected with the equipment or is not successfully read, automatically calling a 5 th built-in EDID, namely 1024 x [email protected], and the audio frequency is PCM 2.0;

3) the EDID of the HDBT port connection equipment can be read again by the equipment in midway plugging or sending an instruction and is stored into the EDID 6;

4) the EDID auto function can be closed by an instruction;

5) 9 EDIDs can be called by the instruction, and the EDID mode is changed into a manual filling mode after the EDID calling instruction is sent;

the manual mode follows the following working logic:

1) host EDID built-in defaults are the following 9, which are 3840 × [email protected], 1920 × [email protected], 1280 × [email protected], 1680 × [email protected], 1024 × [email protected], HDBT1 learning EDID, 1920 × [email protected], 1660 × [email protected], 1440 × [email protected] and all audio modes are PCM 2.0;

2) the built-in EDID can be called through an instruction, and after the built-in EDID is called through a software instruction, the power is cut off and the power is powered on again, the EDID is changed into a manual mode, and the EDID is called finally by the instruction before the power is cut off;

3) if the instruction is manually sent to learn the EDID of the P1 interface, the EDID schema is converted into a manual EDID schema, and the EDID of the P1 interface is directly saved and called.

7. The distribution board card with the automatic switching signal source according to claim 6, wherein: the power-off memory module works in two input signal switching modes of instruction switching and automatic switching, the input port before power-off is memorized, and when the power-off memory module is in automatic switching, if the input source before power-off is not accessed when power-off is powered on after power-off, the interface signal according to the automatic switching principle and the highest priority of the current input signal is input at present again.

8. The distribution board card with the automatic switching signal source according to claim 1, wherein: the dust blowing unit (2) is arranged on a rectangular shell (21) on the fixed plate body (1) and a fan assembly (22) arranged in the rectangular shell (21), an air outlet (211) is formed in one side of the rectangular shell (21), a dust screen (212) is arranged on the other side of the rectangular shell, a through hole (213) is formed in the upper end of the air outlet (211), a positioning groove rail (214) is formed in the lower end of the air outlet (211), and mounting cavities (215) are formed in two sides of one side, provided with the air outlet (211), of the rectangular shell (21);

the fan assembly (22) comprises a fan frame (221) fixedly arranged in the rectangular shell (21) and a fan (222) fixedly arranged in the fan frame (221);

the wind shielding opening piece (23) is movably arranged in an air outlet (211) formed in the rectangular shell (21), the wind shielding opening piece (23) comprises a winding shaft piece (231) arranged in the mounting cavity (215) and a blocking opening piece (232) with one end wound on the winding shaft piece (231) and one end movably arranged in the air outlet (211).

9. The distribution board card with the automatic switching signal source according to claim 8, wherein: the winding shaft piece (231) comprises a rotating shaft (2311) and a baffle plate (2312) fixedly welded at two ends of the rotating shaft (2311), two ends of the rotating shaft (2311) are movably installed on bearing blocks (2314), the bearing blocks (2314) are installed in the installation cavity (215), torsion springs (2313) are movably sleeved at two ends of the rotating shaft (2311), one ends of the torsion springs (2313) are fixedly welded on the baffle plate (2312), and the other ends of the torsion springs are fixedly welded on the bearing blocks (2314).

10. The distribution board card with the automatic switching signal source of claim 9, wherein: keep off mouthful piece (232) including one end fix fender cloth (2321) on pivot (2311) and movable mounting fixed block (2322) in air outlet (211), the other end fixed connection of keeping off cloth (2321) is on fixed block (2322), and the upper end both ends of fixed block (2322) all fixedly are provided with block (2323), and block (2323) block respectively in running through mouth (213) and positioning groove rail (214) to at the side fixed mounting magnet (2324) of fixed block (2322).

Technical Field

The invention relates to the technical field of distribution board cards, in particular to a distribution board card with an automatic switching signal source.

Background

The signal distributor is an instrument for transmitting, converting, isolating, transmitting and calculating various industrial signals in an automatic control system, can be matched with various industrial sensors to retrieve parameter signals and isolate transmitting and transmitting, and meets the requirement of local monitoring and remote data acquisition of users.

When using, current signal distribution board card can not carry out automatic switch-over to the signal source, can not automatic carry out automatic switching-over to the priority of input signal simultaneously, and moreover, current signal distribution board card can fall the dust at the integrated circuit board surface area when using, causes the problem of component heat dissipation badly and short circuit, needs regularly to dismantle to carry out the deashing and handles, unusual inconvenient.

In order to solve the problems, the invention provides a distribution board card with an automatic switching signal source.

Disclosure of Invention

The invention aims to provide a distribution board card with an automatic signal source switching function, which comprises a fixed board body and a dust blowing unit fixedly arranged at one end of the upper end surface of the fixed board body, so that dust cleaning treatment is convenient to carry out, a control port comprises a UART (universal asynchronous receiver/transmitter) and a USB (universal serial bus) communication connection mode and is used for electrically connecting an AV (audio/video) board and a central control CPU (central processing unit) board, and an input signal switching module arranged on the central control CPU board can be used for switching the signal source, so that the problems in the background technology are solved.

In order to achieve the purpose, the invention provides the following technical scheme: a distribution board card with an automatic signal source switching function comprises a fixed board body and a dust blowing unit fixedly installed at one end of the upper end face of the fixed board body, an AV board and a central control CPU board are fixedly installed on the upper end face of the fixed board body, the AV board is provided with a video port, an audio port and a control port, and the control port comprises a UART communication connection mode and a USB communication connection mode and is used for electrically connecting the AV board and the central control CPU board;

the method comprises the following steps that communication between an AV board and a central control CPU board is carried out through a UART interface, control of the central control CPU board on the AV board and collection of state data of the AV board are achieved, and when the state of a video signal interface changes, a main MCU of the AV board actively reports the state change through a serial port;

the communication between the AV board and the central control CPU board is carried out through the USB interface, the control of the central control CPU board on the AV board and the collection of each state data of the AV board are realized, and when the state of the video signal interface changes, the main MCU of the AV board actively reports the state change through the USB interface;

the central control CPU board comprises an input signal switching module for switching HDMI input signals and VGA input signals and an output signal control module for controlling HDMI output and VGA output, and is also provided with an EDID module for expanding display identification data and a power-off memory module capable of performing power-off protection memory.

Furthermore, the video port comprises an HDMI input and a VGA input, a 5V signal of the HDMI acquires the state of the HMDI input channel, whether HDMI signal source equipment is accessed is detected through the 5V signal, a 5 th pin and a 10 th pin of the VGA signal equipment interface are communicated and grounded, and the detection of the physical connection state of user equipment connected with the VGA input interface is realized.

Furthermore, the video port comprises HDMI output and VGA output, the HPD signal of the HDMI acquires the state of the HMDI output channel, namely, whether the HDMI display device is accessed is detected through the HPD signal, the 5 th pin and the 10 th pin of the VGA signal device interface are communicated and grounded, and the detection of the physical connection state of the user equipment connected with the VGA output interface is realized.

Further, the communication connection modes of the UART and the USB follow the following two signal communication logics:

1) the input of HDMI audio and video needs to be switched synchronously;

2) when VGA is selected by input, VGA can realize no video signal, only audio signal is still transmitted to 2 output channels 3.5, and 3.5 input audio is not output to HDMI.

Furthermore, the input signal switching module sets a switching mode through an instruction, and supports two modes of instruction switching and automatic switching;

the automatic switching follows the principle of last-in-first-out:

1) when power is on, the HDMI1 has the highest priority, the priority is sequentially reduced from the HDMI1, the HDMI2, the HDMI3 and the VGA +3.5, and when no signal with high priority is detected, the signal is automatically converted into a signal with a lower priority;

2) when a new input signal is accessed, automatically switching to a new input channel;

3) the automatic switching mode is compatible with manual switching, namely, in the automatic switching mode, instruction switching is supported.

Further, the EDID module includes both an automatic mode and a manual mode, wherein the automatic mode follows the following working logic:

1) when the EDID is electrified, learning the EDID of the 1 st HDBT1 port connecting device, automatically storing the EDID in an EDID6, if the EDID is learned to be in a DVI format, automatically converting the EDID into the HDMI, wherein the audio frequency is PCM2.0, and reading the EDID again and covering the EDID data of the last time when the EDID is electrified;

2) if the HDBT is not connected with the equipment or is not successfully read, automatically calling a 5 th built-in EDID, namely 1024 x [email protected], and the audio frequency is PCM 2.0;

3) the EDID of the HDBT port connection equipment can be read again by the equipment in midway plugging or sending an instruction and is stored into the EDID 6;

4) the EDID auto function can be closed by an instruction;

5) 9 EDIDs can be called by the instruction, and the EDID mode is changed into a manual filling mode after the EDID calling instruction is sent;

the manual mode follows the following working logic:

1) host EDID built-in defaults are the following 9, which are 3840 × [email protected], 1920 × [email protected], 1280 × [email protected], 1680 × [email protected], 1024 × [email protected], HDBT1 learning EDID, 1920 × [email protected], 1660 × [email protected], 1440 × [email protected] and all audio modes are PCM 2.0;

2) the built-in EDID can be called through an instruction, and after the built-in EDID is called through a software instruction, the power is cut off and the power is powered on again, the EDID is changed into a manual mode, and the EDID is called finally by the instruction before the power is cut off;

3) if the instruction is manually sent to learn the EDID of the P1 interface, the EDID schema is converted into a manual EDID schema, and the EDID of the P1 interface is directly saved and called.

And further, the power-off memory module works in two input signal switching modes of instruction switching and automatic switching, the input port before power-off is memorized, and when the power-off memory module is in automatic switching, if the input source before power-off is not accessed when the power-off memory module is powered on after power-off, the input port is input again according to the automatic switching principle and the highest priority interface signal of the current input signal.

Furthermore, the dust blowing unit is arranged on a rectangular shell on the fixed plate body and a fan assembly arranged in the rectangular shell, one side of the rectangular shell is provided with an air outlet, the other side of the rectangular shell is provided with a dust screen, the upper end of the air outlet is provided with a through hole, the lower end of the air outlet is provided with a positioning groove rail, and two sides of one side of the rectangular shell, which is provided with the air outlet, are provided with mounting cavities;

the fan assembly comprises a fan frame fixedly arranged in the rectangular shell and a fan fixedly arranged in the fan frame;

the wind shielding opening piece is movably arranged in the air outlet formed in the rectangular shell, the wind shielding opening piece comprises a winding shaft piece and a wind shielding opening piece, the winding shaft piece is arranged in the installation cavity, one end of the wind shielding opening piece is wound on the winding shaft piece, and one end of the wind shielding opening piece is movably arranged in the air outlet.

Further, the rolling shaft piece comprises a rotating shaft and baffle plates fixedly welded at two ends of the rotating shaft, the two ends of the rotating shaft are movably mounted on the bearing blocks, the bearing blocks are mounted in the mounting cavities, torsion springs are movably sleeved at two ends of the rotating shaft, one end of each torsion spring is fixedly welded on the baffle plate, and the other end of each torsion spring is fixedly welded on the corresponding bearing block.

Further, keep off a mouthful piece and include that one end is fixed and is changeed epaxial fender cloth and movable mounting at the intraoral fixed block of air outlet, the other end fixed connection that keeps off the cloth on the fixed block, and the upper end both ends of fixed block all fixedly are provided with the block piece, and the block piece block respectively in running through mouthful and positioning groove rail to at the side fixed mounting magnet of fixed block.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention provides a distribution board card with an automatic switching signal source, which uses two communication connection modes of UART and USB for the electrical connection of an AV board and a central control CPU board, an input signal switching module for switching HDMI input signals and VGA input signals is arranged on the central control CPU board, the input signal switching module supports two types of instruction switching and automatic switching in an instruction setting switching mode, the automatic switching follows the principle of last-in first-out, at power-up, HDMI1 has the highest priority, with priority decreasing from HDMI1, HDMI2, HDMI3, VGA +3.5, when detecting a high priority no-signal, automatically switching to a low priority signal, when a new input signal is accessed, the input signal switching module is used for switching to a new input channel automatically, conveniently switching signals input by the HDMI and the VGA, and the priority can be ensured, and the input channel can be replaced to a new input channel in time when a new signal is input.

2. The distribution board card with the automatic switching signal source, provided by the invention, has the advantages that the outage memory module is arranged, the outage memory module works in two input signal switching modes of instruction switching and automatic switching, the input port before outage is memorized, the input signal before outage can be conveniently and timely judged to be the current input signal after being electrified, when the input signal is automatically switched, if the input source before outage is not accessed when being electrified again after outage, the input signal is input again according to the automatic switching principle and according to the highest priority interface signal of the current input signal, and compared with the traditional signal distribution board card, the distribution board card has the outage memory function and is more convenient.

3. The invention provides a distribution board card with an automatic switching signal source, one end of a blocking cloth is fixed on a rotating shaft, the other end of the blocking cloth is connected with a fixed block movably arranged in an air outlet, and the two ends of the rotating shaft are movably sleeved with torsional springs, one end of each torsional spring is fixedly welded on the baffle plate, the other end of each torsional spring is fixedly welded on the bearing block, the rotating shaft is movably arranged in an installation cavity arranged in the rectangular shell through the bearing block, a fan is arranged in the rectangular shell, when the distribution board card needs to be cleaned, the fan is started to blow air to the fixed plate body, dust on the AV plate and the central control CPU plate is blown off, the disassembly for cleaning the dust is not needed to be more convenient, when the dust is cleaned, the fixed block can be moved to pull out the blocking cloth, the air outlet is separated and blocked, and the size of the air outlet is adjusted, so that the purpose of adjusting the air outlet force is achieved, and the ash removal treatment is more conveniently carried out.

Drawings

Fig. 1 is a block diagram of a distribution board card with an automatic switching signal source according to the present invention;

fig. 2 is a schematic view of a connection structure between a dust blowing unit and a fixed plate of a distribution board card with an automatic switching signal source according to the present invention;

fig. 3 is a cross-sectional view of a rectangular housing of a distribution board card with an automatic switching signal source according to the present invention;

fig. 4 is a schematic structural diagram of a wind-shielding mouth piece of a distribution board card with an automatic switching signal source according to the present invention;

fig. 5 is an enlarged view of a portion a of the distribution board with an automatic switching signal source according to the present invention in fig. 4.

In the figure: 1. fixing the plate body; 2. a dust blowing unit; 21. a rectangular housing; 211. an air outlet; 212. a dust screen; 213. a through opening; 214. positioning the groove rail; 215. a mounting cavity; 22. a fan assembly; 221. a fan frame; 222. a fan; 23. a weather shield; 231. rolling the shaft piece; 2311. a rotating shaft; 2312. a baffle plate; 2313. a torsion spring; 2314. a bearing block; 232. a mouth stop member; 2321. blocking cloth; 2322. a fixed block; 2323. a clamping block; 2324. and a magnet.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1 and 2, a distribution board card with an automatic signal source switching function includes a fixed board 1 and a dust blowing unit 2 fixedly installed at one end of an upper end surface of the fixed board 1, and an AV board and a central control CPU board are fixedly installed on the upper end surface of the fixed board 1, where the AV board is provided with a video port, an audio port and a control port, and the control port includes a UART and a USB for electrically connecting the AV board and the central control CPU board.

The method comprises the following steps that communication between an AV board and a central control CPU board is carried out through a UART interface, control of the central control CPU board on the AV board and collection of state data of the AV board are achieved, and when the state of a video signal interface changes, a main MCU of the AV board actively reports the state change through a serial port; and when the state of the video signal interface changes, the main MCU of the AV board actively reports the state change through the USB interface.

The central control CPU board comprises an input signal switching module for switching HDMI input signals and VGA input signals and an output signal control module for controlling HDMI output and VGA output, and is also provided with an EDID module for expanding display identification data and a power-off memory module capable of performing power-off protection memory.

The video port comprises HDMI input and VGA input, the 5V signal of the HDMI acquires the state of an HMDI input channel, whether HDMI signal source equipment is accessed through 5V signal detection or not is detected, the 5 th pin and the 10 th pin of the VGA signal equipment interface are communicated and grounded, the detection of the physical connection state of user equipment connected with the VGA input interface is realized, the video port comprises HDMI output and VGA output, the HPD signal of the HDMI acquires the state of the HMDI output channel, namely whether HDMI display equipment is accessed through HPD signal detection or not is detected, the 5 th pin and the 10 th pin of the VGA signal equipment interface are communicated and grounded, and the detection of the physical connection state of the user equipment connected with the VGA output interface is realized.

It should be noted that, the two communication connection modes of UART and USB follow the following two signal communication logics:

1) the input of HDMI audio and video needs to be switched synchronously;

2) when VGA is selected by input, VGA can realize no video signal, only audio signal is still transmitted to 2 output channels 3.5, and 3.5 input audio is not output to HDMI.

Furthermore, the input signal switching module sets a switching mode through an instruction, and supports two modes of instruction switching and automatic switching;

the automatic switching follows the principle of last-in-first-out:

1) when power is on, the HDMI1 has the highest priority, the priority is sequentially reduced from the HDMI1, the HDMI2, the HDMI3 and the VGA +3.5, and when no signal with high priority is detected, the signal is automatically converted into a signal with a lower priority;

2) when a new input signal is accessed, automatically switching to a new input channel;

3) the automatic switching mode is compatible with manual switching, namely, in the automatic switching mode, instruction switching is supported.

Further, the EDID module includes both an automatic mode and a manual mode, wherein the automatic mode follows the following working logic:

1) when the EDID is electrified, learning the EDID of the 1 st HDBT1 port connecting device, automatically storing the EDID in an EDID6, if the EDID is learned to be in a DVI format, automatically converting the EDID into the HDMI, wherein the audio frequency is PCM2.0, and reading the EDID again and covering the EDID data of the last time when the EDID is electrified;

2) if the HDBT is not connected with the equipment or is not successfully read, automatically calling a 5 th built-in EDID, namely 1024 x [email protected], and the audio frequency is PCM 2.0;

3) the EDID of the HDBT port connection equipment can be read again by the equipment in midway plugging or sending an instruction and is stored into the EDID 6;

4) the EDID auto function can be closed by an instruction;

5) 9 EDIDs can be called by the instruction, and the EDID mode is changed into a manual filling mode after the EDID calling instruction is sent;

the manual mode follows the following working logic:

1) host EDID built-in defaults are the following 9, which are 3840 × [email protected], 1920 × [email protected], 1280 × [email protected], 1680 × [email protected], 1024 × [email protected], HDBT1 learning EDID, 1920 × [email protected], 1660 × [email protected], 1440 × [email protected] and all audio modes are PCM 2.0;

2) the built-in EDID can be called through an instruction, and after the built-in EDID is called through a software instruction, the power is cut off and the power is powered on again, the EDID is changed into a manual mode, and the EDID is called finally by the instruction before the power is cut off;

3) if the instruction is manually sent to learn the EDID of the P1 interface, the EDID schema is converted into a manual EDID schema, and the EDID of the P1 interface is directly saved and called.

The method is characterized in that two communication connection modes of UART and USB are used for electrically connecting an AV board and a central control CPU board, an input signal switching module for switching HDMI input signals and VGA input signals is arranged on the central control CPU board, the input signal switching module sets a switching mode through an instruction, two modes of instruction switching and automatic switching are supported, the automatic switching follows the principle of last-in first-out, the HDMI1 has the highest priority when the CPU is powered on, the priority is lowered from HDMI1, HDMI2, HDMI3 and VGA +3.5 in sequence, when no signal with the high priority is detected, the signal is automatically converted into a signal with the lower priority, when a new input signal is accessed, the signal is automatically switched to a new input channel, the signals input into the AV board and VGA are conveniently switched through the input signal switching module, the priority can be guaranteed, and the new input channel can be timely replaced when the new signal is input.

The power-off memory module works in two input signal switching modes of instruction switching and automatic switching, memorizes an input port before power-off, when the power-off memory module is in automatic switching, if an input source before power-off is not accessed when power is on again after power-off, the input port before power-off is input again according to the highest priority interface signal of the current input signal according to the automatic switching principle, and the power-off memory module works in the two input signal switching modes of instruction switching and automatic switching by setting the power-off memory module, memorizes the input port before power-off to conveniently and timely judge that the input signal before power-off is the current input signal after power-on, when the power-off memory module is in automatic switching, if the input source before power-off is not accessed when power is on again after power-off, the input port before power-off is input again according to the highest priority interface signal of the current input signal according to the automatic switching principle, and compared with the traditional signal distribution board card, the power-off memory function is provided, more convenient.

Referring to fig. 3-4, the dust blowing unit 2 is installed on a rectangular housing 21 of the fixed plate 1 and a fan assembly 22 installed in the rectangular housing 21, an air outlet 211 is formed in one side of the rectangular housing 21, a dust screen 212 is installed in the other side of the rectangular housing 21, a through hole 213 is formed in an upper end of the air outlet 211, a positioning groove rail 214 is formed in a lower end of the air outlet 211, installation cavities 215 are formed in two sides of one side of the air outlet 211 formed in the rectangular housing 21, the fan assembly 22 includes a fan frame 221 fixedly installed in the rectangular housing 21 and a fan 222 fixedly installed in the fan frame 221, a wind shielding opening 23 is movably installed in the air outlet 211 formed in the rectangular housing 21, the wind shielding opening 23 includes a wind-up shaft 231 installed in the installation cavity 215 and a wind shielding member 232 with one end wound up on the wind-up shaft 231 and one end movably installed in the air outlet 211.

Referring to fig. 4-5, the wind-up shaft 231 includes a rotation shaft 2311 and a baffle 2312 fixedly welded to both ends of the rotation shaft 2311, both ends of the rotation shaft 2311 are movably mounted on the bearing blocks 2314, the bearing blocks 2314 are mounted in the mounting cavity 215, a torsion spring 2313 is movably sleeved on both ends of the rotation shaft 2311, one end of the torsion spring 2313 is fixedly welded to the baffle 2312, and the other end is fixedly welded to the bearing blocks 2314.

Referring to fig. 4, the opening blocking member 232 includes a cloth 2321 having one end fixed on the rotating shaft 2311 and a fixed block 2322 movably installed in the air outlet 211, the other end of the cloth 2321 is fixedly connected to the fixed block 2322, both ends of the upper end of the fixed block 2322 are fixedly provided with a fastening block 2323, the fastening block 2323 is respectively fastened in the through opening 213 and the positioning groove rail 214, a magnet 2324 is fixedly installed on the side surface of the fixed block 2322, one end of the cloth 2321 is fixed on the rotating shaft 2311, the other end is connected to the fixed block 2322 movably installed in the air outlet 211, both ends of the rotating shaft 2311 are movably sleeved with a torsion spring 2313, one end of the torsion spring 2313 is fixedly welded on the baffle 2312, the other end is fixedly welded on the bearing block 2314, the rotating shaft 2311 is movably installed in the installation cavity 215 formed in the rectangular housing 21 through the bearing block 2314, and the blower 222 is installed in the rectangular housing 21, when ash removal is required, open fan 222 and blow to going up on the fixed plate body 1, will blow off in the dust on AV board and well accuse CPU board, need not to dismantle the deashing more convenient, when the deashing, the accessible removes fixed block 2322, will keep off cloth 2321 and pull out, separates the fender to air outlet 211, adjusts the size of air outlet 211 to reach the purpose of adjusting the air-out dynamics, the more convenient deashing of carrying on is handled.

In summary, the following steps: the invention provides a distribution board card with an automatic switching signal source, which uses two communication connection modes of UART and USB for the electrical connection of an AV board and a central control CPU board, an input signal switching module for switching HDMI input signals and VGA input signals is arranged on the central control CPU board, the input signal switching module supports two types of instruction switching and automatic switching in an instruction setting switching mode, the automatic switching follows the principle of last-in first-out, at power-up, HDMI1 has the highest priority, with priority decreasing from HDMI1, HDMI2, HDMI3, VGA +3.5, when detecting a high priority no-signal, automatically switching to a low priority signal, when a new input signal is accessed, the input signal switching module is used for switching to a new input channel automatically, conveniently switching signals input by the HDMI and the VGA, the priority can be ensured, and a new input channel can be replaced in time when a new signal is input; by arranging the power-off memory module, the power-off memory module works in two input signal switching modes of instruction switching and automatic switching, the input port before power-off is memorized, so that the input signal before power-off can be conveniently and timely judged to be the current input signal after power-on, and when the input signal before power-off is automatically switched, if the input source before power-off is not accessed when power-on is carried out again after power-off, the input signal is input again according to the automatic switching principle and the highest priority interface signal of the current input signal; one end of a blocking cloth 2321 is fixed on the rotating shaft 2311, the other end of the blocking cloth 2321 is connected with a fixed block 2322 movably installed in the air outlet 211, torsion springs 2313 are movably sleeved at two ends of the rotating shaft 2311, one end of each torsion spring 2313 is fixedly welded on the corresponding blocking plate 2312, the other end of each torsion spring 2314 is fixedly welded on a bearing block 2314, the rotating shaft 2311 is movably installed in an installation cavity 215 formed in the rectangular shell 21 through the bearing block 2314, a fan 222 is installed in the rectangular shell 21, when the distribution board card needs to be cleaned, the fan 222 is started to blow air onto the fixed plate body 1, dust on the AV plate and the central control CPU plate is blown off, the cleaning and the cleaning are not needed to be disassembled, the dust is more convenient, when the dust is cleaned, the blocking cloth 2321 is pulled out through moving the fixed block 2322, the air outlet 211 is blocked, the size of the air outlet 211 is adjusted, and accordingly the purpose of adjusting the air outlet force is achieved, and the dust cleaning and the dust is more convenient.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.