Light source control system for machine vision

Abstract

The utility model discloses a light source control system for machine vision. The light source control system comprises a controller; the control circuit comprises an MOS tube Q5, the MOS tube Q5 is an N-type MOS tube, a grid electrode G of the MOS tube Q5 is connected with the controller through a first circuit, a drain electrode D of the MOS tube Q5 is connected with one wiring end of a wiring terminal P6 through a third circuit, the other wiring end of the wiring terminal is connected with the output end of the power supply, and the light source is installed on the wiring terminal; the source electrode of the MOS tube Q5 is grounded through a fourth line; and the controller can output voltage through the first line so as to control the on / off of the MOS tube Q5 and further control the on / off of the light source.

Description

TECHNICAL FIELD

[0001] The utility model relates to machine vision field especially relates to a light source control system for machine vision. BACKGROUND

[0002] In industry, the workpiece in processing is detected by machine vision, and the light source and camera are used in cooperation in detection, and the required picture is shot. The control of light source is very important in shooting, and the light source is only opened in shooting and closed in ending shooting, but the workpiece moves fast on the flow line, so the light source needs to be opened and closed fast, and the fast opening and closing will cause the current to be too large or too small on the line, and if the current is not closed in time, the light source will be damaged, and if the current is too small, the energy consumption will be wasted, so how to control the opening and closing of light source and how to protect the light source are particularly important. SUMMARY

[0003] The utility model discloses a kind of light source control systems for machine vision, the control system is switched to light source by using smaller voltage, and it can also automatically power off when the current of light source is too large or too small.

[0004] To achieve the above object, the utility model adopts the technical scheme that a kind of light source control system for machine vision, comprising:

[0005] Controller;

[0006] Control circuit, including MOS tube Q5, the MOS tube Q5 is N-type MOS tube, the gate G of the MOS tube Q5 is connected controller by first line, the drain D of the MOS tube Q5 is connected the one terminal of connection terminal P6 by third line, the other terminal of connection terminal is connected the output end of power supply, the light source is installed on connection terminal;The source of the MOS tube Q5 is grounded by fourth line 4;Controller can output voltage by first line, and then can control the conduction or disconnection of MOS tube Q5, and then control the opening and closing of light source.

[0007] Preferably, the control circuit further includes a second line, one end of the second line is connected to the output end of the power supply, and the other end is connected to the third line, and a resistor R21 is arranged on the second line.

[0008] Preferably, the control circuit further comprises a resistor R28 arranged on the fourth line, and a fifth line, one end of the fifth line is connected to the fourth line between the MOS tube Q5 and the resistor R28, and the other end of the fifth line is connected to the controller, the controller can obtain the voltage on the resistor R28, and then calculate the current of the light source through the voltage and the resistance of the resistor R28, when the current through the light source is too large or too small, the controller can control the MOS tube Q5 to be closed.

[0009] Preferably, a resistor R27 is arranged on the fifth line, and the control circuit further comprises a sixth line, one end of the sixth line is connected to the fifth line on the downstream side of the resistor R27, and the other end of the sixth line is grounded, and a capacitor C16 is arranged on the sixth line, and the resistor R27 and the capacitor C16 constitute an RC filter circuit.

[0010] Preferably, the control circuit further comprises a seventh line, one end of the seventh line is connected to the fifth line on the end connected to the controller, and the other end of the seventh line is grounded, and a voltage stabilizing diode D8 is arranged on the seventh line, when the voltage stabilizing diode D8 is not broken down, the voltage stabilizing diode D8 allows the seventh line to be unidirectionally conducted along the direction from the ground end to the fifth line.

[0011] Compared with the prior art, the utility model has the following beneficial effects:

[0012] 1) the utility model discloses the switch of the light source using the controller control MOS tube, and the switch of the light source is controlled using smaller voltage;Meanwhile, the controller can obtain the current of the circuit through the light source in real time, and timely controls the switch of the light source according to the size of the current;

[0013] 2) the utility model can use external equipment such as mobile phone, notebook computer as power supply and provide different output voltages through the internal boost circuit and voltage stabilizing circuit, and then portable function can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is the control circuit diagram of the utility model;

[0015] Figure 2 It is the external interface diagram;

[0016] Figure 3 It is the circuit diagram of the boost circuit;

[0017] Figure 4 It is the circuit diagram of the voltage stabilizing circuit;

[0018] Figure 5 It is the circuit diagram of the controller. DETAILED DESCRIPTION

[0019] The following description is used to disclose the utility model so that those skilled in the art can implement the utility model. The preferred embodiments in the following description are only as examples, and other obvious variants can be conceived by those skilled in the art.

[0020] A light source control system for machine vision, comprising a controller and a control circuit, the control circuit comprising a MOS tube Q5, the MOS tube Q5 being an N-type MOS tube, the gate G of the MOS tube Q5 being connected to the controller through a first line 1, the drain D of the MOS tube Q5 being connected to one terminal of a terminal P6 through a third line 3, the other terminal of the terminal P6 being connected to the output terminal of a power supply, and the terminal P6 being used for connecting a light source. The source of the MOS tube Q5 is grounded through a fourth line 4. The controller can output a voltage through the first line 1, thereby being able to control the turn-on or turn-off of the MOS tube Q5. When the controller outputs a high level to the first line 1, the MOS tube Q5 is turned on, the third line 3 and the fourth line 4 are connected, and the light source is turned on. When the controller outputs a low level to the first line 1, the MOS tube Q5 is turned off, and the light source is turned off.

[0021] The control circuit further comprises a second line 2, one end of the second line 2 being connected to the output terminal of the power supply, and the other end being connected to the third line 3. A resistor R21 is arranged on the second line 2. The resistor R21 functions as a dummy load. If there is no resistor R21, the drain of the MOS tube Q5 is in a high-impedance state, is easily disturbed by the outside world, causes the drain voltage to be unstable, and further causes the MOSFET to be mis-switched, and even can cause the circuit to be in a high-frequency oscillation or unstable state. Of course, in practice, the resistor R21 can also be omitted.

[0022] Only a small load current needs to be provided, but an excessively large current is not required, so a relatively large resistance is good

[0023] The control circuit further comprises a resistor R28 arranged on the fourth line 4 and a fifth line 5. The resistor R28 is a sampling resistor. One end of the fifth line 5 is connected to the part of the fourth line 4 between the MOS tube Q5 and the resistor R28, and the other end of the fifth line 5 is connected to the controller. The controller can obtain the voltage on the resistor R28, and further can obtain the current passing through the light source according to the voltage and the resistance of the resistor R28. When the current passing through the light source is excessively large or small, the controller can control the MOS tube Q5 to be turned off.

[0024] A resistor R27 is arranged on the fifth line 5. The control circuit further comprises a sixth line 6, one end of the sixth line 6 being connected to the side of the fifth line 5 downstream of the resistor R27, and the other end being grounded. A capacitor C16 is arranged on the sixth line 6. The resistor R27 and the capacitor C16 constitute an RC filter circuit.

[0025] The control circuit further comprises a seventh line 7, one end of which is connected to the end of the fifth line 5 connected to the controller, and the other end is grounded, and a voltage stabilizing diode D8 is arranged on the seventh line 7, which allows the seventh line 7 to conduct in one direction from the ground end to the fifth line 5 when not broken down. When the voltage output to the controller on the fifth line 5 exceeds the breakdown voltage of the voltage stabilizing diode D8, the voltage stabilizing diode D8 conducts reversely, thereby preventing the voltage output to the controller on the fifth line 5 from exceeding the predetermined value, and protecting the controller.

[0026] The system further comprises an external interface JP1, a voltage boosting circuit and a voltage stabilizing circuit. The external interface JP1 is used to connect with external devices such as mobile phones, notebook computers, etc., and the entire system is powered by the external devices. The external interface JP1 has a first output end, which can output the same voltage as the external device, and the voltage of the mobile phone and notebook computer is generally 3.7V. The voltage boosting circuit has a first input end for connecting the first output end. The voltage boosting circuit comprises a voltage stabilizing chip U1, an eighth line 8, a second output end, an inductor L1, a diode D1, a capacitor C1 and a capacitor C2. One end of the eighth line 8 is connected to the first input end, and the other end is connected to the second output end. The inductor L1 and the diode D1 are arranged in sequence on the eighth line 8 in the direction from the first input end to the second output end. The diode D1 allows the current on the eighth line 8 to flow in one direction from the first input end to the second output end. One end of the capacitor C1 and the capacitor C2 is connected to the side of the eighth line 8 close to the output end. The voltage stabilizing chip U1 is TPS55340. The pins SW1, SW15 and SW16 of the voltage stabilizing chip U1 are respectively connected to the part of the eighth line 8 between the inductor L1 and the diode D1. The voltage stabilizing chip U1 has a MOSFET switch inside. When the MOSFET switch is turned on, the voltage input from the first input end enters the inside of the voltage stabilizing chip U1, the inductor starts to store electric energy, and the capacitor C1 and the capacitor C2 discharge at the second output end. When the MOSFET switch is turned off, the inductor L1 starts to discharge, and the inductor L1 outputs voltage to the second output end through the diode D1, while charging the capacitor C1 and the capacitor C2. Through the inductor L1, the capacitor C1 and the capacitor C2, voltage boosting can be achieved. In practice, the second output end outputs a voltage of 12V. The external interface JP1 has a first enable output end TP8, and the voltage stabilizing chip U1 has a first enable input end EN. The first enable output end TP8 is connected to the first enable input end EN, so that the switch of the voltage stabilizing chip U1 can be controlled through the external device. The voltage stabilizing chip U1 uses an existing chip, and the specific principle is not described here. The second output end is the output end of the power supply.

[0027] The voltage stabilizing circuit comprises a linear voltage stabilizing chip U2, an input end of the linear voltage stabilizing chip U2 is connected with the first output end through a ninth line 9, an output end of the linear voltage stabilizing chip U2 is connected with a tenth line 10, and a power supply end of the controller is connected with the tenth line 10, namely, the controller is powered by the linear voltage stabilizing chip U2. The linear voltage stabilizing chip U2 has a second enable input end EN, and the second enable input end EN is connected with the first enable output end EN. When the voltage output by the external device through the first enable output end EN is lower than a predetermined value (0.2V), the voltage stabilizing circuit and the voltage stabilizing circuit stop outputting, the microcontroller and the light source are powered off, and the continuous power supply to the circuit at a low voltage is avoided, and the energy consumption is reduced.

[0028] The basic principle, main features and advantages of the utility model are shown and described above. It should be understood by those skilled in the art that the utility model is not limited by the above-mentioned embodiments, and the above-mentioned embodiments and the description in the specification are only the principles of the utility model. The utility model can have various changes and improvements without departing from the spirit and scope of the utility model, and these changes and improvements all fall within the scope of the utility model claimed. The protection scope required by the utility model is defined by the appended claims and their equivalents.

Claims

1. A light source control system for machine vision, characterized in that, include: Controller; The control circuit includes a MOSFET Q5, which is an N-type MOSFET. The gate G of the MOSFET Q5 is connected to the controller via a first line, and the drain D of the MOSFET Q5 is connected to one terminal of a terminal block P6 via a third line. The other terminal of the terminal block is connected to the output terminal of the power supply. The light source is mounted on the terminal block. The source of the MOSFET Q5 is grounded via a fourth line. The controller can output a voltage through the first line to control the conduction or disconnection of the MOSFET Q5, thereby controlling the switching of the light source.

2. The light source control system for machine vision according to claim 1, characterized in that, The control circuit also includes a second line, one end of which is connected to the output terminal of the power supply, and the other end is connected to a third line. A resistor R21 is set on the second line.

3. A light source control system for machine vision according to claim 2, characterized in that, The control circuit also includes a resistor R28 on the fourth line and a fifth line. One end of the fifth line is connected to the part of the fourth line between the MOSFET Q5 and the resistor R28, and the other end of the fifth line is connected to the controller. The controller can obtain the voltage on the resistor R28 and then calculate the current of the light source by the voltage and the resistance value of the resistor R28. When the current through the light source is too large or too small, the controller can control the MOSFET Q5 to turn off.

4. A light source control system for machine vision according to claim 3, characterized in that, A resistor R27 is provided on the fifth line. The control circuit also includes a sixth line. One end of the sixth line is connected to the side of the fifth line downstream of the resistor R27, and the other end is grounded. A capacitor C16 is provided on the sixth line. The resistor R27 and the capacitor C16 form an RC filter circuit.

5. A light source control system for machine vision according to claim 4, characterized in that, The control circuit also includes a seventh line, one end of which is connected to the end of the fifth line that is connected to the controller, and the other end is grounded. A Zener diode D8 is provided on the seventh line. When the Zener diode D8 is not broken down, the Zener diode D8 enables the seventh line to conduct unidirectionally from the ground end to the fifth line.

6. A light source control system for machine vision according to claim 5, characterized in that, Also includes: An external interface for connecting external devices, having a first output terminal and a first enable output terminal; The boost circuit has a first input terminal, a second output terminal, and a first enable input terminal. The first input terminal is connected to the first output terminal, and the output terminal of the power supply is the second output terminal. A voltage regulator circuit has its input terminal connected to the first output terminal, its second enable input terminal connected to the first enable output terminal, and its output terminal connected to the controller to supply power to the controller.

7. A light source control system for machine vision according to claim 6, characterized in that, The external device is a mobile phone or a laptop computer.

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