Lighting control system and power supply unit

Abstract

This invention provides a lighting control system that can accurately identify lighting circuits connected to a power supply. [Solution] A control system for controlling the manner in which light is emitted, comprising: a power supply device having a positive output terminal and a negative output terminal connected to a power supply circuit and a lighting signal output terminal; a lighting circuit device having a lighting circuit connected to each of the output terminals via a cable and controlling lighting; a discrimination mechanism for determining the type of lighting circuit, wherein the discrimination mechanism is provided in the lighting circuit and an oscillation circuit outputs a pulse signal set according to the type of lighting circuit to the positive output terminal or the negative output terminal; a discrimination circuit provided in the power supply device for determining the type of lighting circuit based on the received pulse signal; and a switching circuit for switching the conductive destination of the positive output terminal or the negative output terminal to which the pulse signal is input between the power supply circuit and the discrimination circuit.

Description

[[Technical Field]]

[0001] The present invention relates to a lighting control system and a power supply device. [[Background Art]]

[0002] Conventionally, as shown in Patent Document 1, some light irradiation systems used for surface inspection of a workpiece include: a light irradiation device provided with a light source such as an LED; a power supply device that supplies electric power to the light irradiation device; and a lighting circuit device that relays current supplied from the power supply device to the light irradiation device. In this system, by arranging a capacitor for auxiliary current supply and a switching element in the lighting circuit device that relays power between the light irradiation device and the power supply device, the lighting circuit device can be reduced in size and arranged in the vicinity of the light irradiation device. As a result, the substantial length of the power supply cable can be shortened, light emission delay and noise can be reduced, and high-speed light emission can be achieved. [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] Japanese Patent Application Laid-Open No. 2023-088785 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] By the way, in the light irradiation system as described above, when the lighting circuit device is connected to the power supply device, the power supply device cannot determine the type of the lighting circuit device, so the power supply device may not be able to output an appropriate lighting signal to the lighting circuit device. For example, if the lighting circuit device is a so-called overdrive type that outputs a drive current exceeding the maximum rated current specified for continuous lighting of the light source, excessive current will flow to the light irradiation device when an appropriate lighting signal is not output from the power supply device, which may lead to failure of the light irradiation device.

[0005] This invention was made to solve these problems, and its main objective is to provide a lighting control system that can accurately identify lighting circuits connected to a power supply. [Means for solving the problem]

[0006] In other words, the lighting control system according to the present invention supplies power to a light irradiation device and controls its light emission mode, and comprises a power supply device having a positive output terminal and a negative output terminal connected to a power supply circuit and a lighting signal output terminal, a lighting circuit device connected to each of the output terminals via a cable and having a lighting circuit that supplies power to the light irradiation device and controls lighting, and a discrimination mechanism for determining the type of lighting circuit, wherein the discrimination mechanism comprises an oscillation circuit provided in the lighting circuit device that outputs a pulse signal set according to the type of lighting circuit to the positive output terminal or the negative output terminal via the cable, a discrimination circuit provided in the power supply device that determines the type of lighting circuit based on the received pulse signal, and a switching circuit that switches the conductive destination of the positive output terminal or the negative output terminal to which the pulse signal is input between the power supply circuit and the discrimination circuit.

[0007] In such a lighting control system, the lighting circuit device is equipped with an oscillator circuit that outputs a pre-set pulse signal according to the type of lighting circuit, and the power supply device is equipped with a discrimination circuit that determines the type of lighting circuit based on the pulse signal output from the oscillator circuit. Therefore, by connecting the lighting circuit device to the power supply device, the power supply device can automatically determine the type of lighting circuit. Furthermore, since the discrimination is based on a digital signal, such as a pulse signal, it is possible to make a more accurate discrimination than if the discrimination were based on an analog signal, such as an analog voltage value. Furthermore, since the power supply unit is configured to switch the destination of the output terminal (negative or positive output terminal) to which the pulse signal is input between the power supply circuit and the discrimination circuit, power supply and discrimination of the type of lighting circuit can be achieved with a single output terminal. This makes it possible to add a function to discriminate the type of lighting circuit without increasing the number of output terminals in the power supply unit. Furthermore, identifying the type of lighting circuit means determining the lighting circuit configured according to whether the light irradiation device operates at a voltage of 24V or 12V, whether it operates in so-called overdrive mode, constant current control mode, or constant voltage control mode. This allows for control according to the type of lighting circuit.

[0008] Furthermore, in the lighting control system, the lighting circuit device is equipped with a charge / discharge circuit that performs charging and discharging, and it is preferable that the charge / discharge circuit is charged while the positive output terminal and the negative output terminal are conductive to the power supply circuit, and when the destination of the conductive connection of the positive output terminal or the negative output terminal switches to the discrimination circuit, discharge occurs from the charge / discharge circuit to the oscillation circuit. In this way, when the oscillation circuit of the lighting circuit device and the discrimination circuit of the power supply device are in conductivity, power can be supplied from the charging / discharging circuit to the oscillation circuit, thereby enabling pulse oscillation operation.

[0009] Furthermore, it is preferable that, when the type of lighting circuit is determined by the discrimination circuit in the lighting control system, the switching circuit switches the destination of the positive output terminal or the negative output terminal to which the pulse signal is input to the power supply circuit, and the lighting circuit starts supplying power to the light irradiation device. In this way, after determining the type of lighting circuit, the switching circuit connects the positive or negative output terminal of the power supply unit to the power supply circuit, thereby supplying a stable DC current to the lighting circuit unit.

[0010] Another specific embodiment of the lighting control system is one in which the discrimination circuit determines the type of lighting circuit based on the duty cycle or pulse width of the received pulse signal.

[0011] Furthermore, an embodiment that demonstrates the effects of the present invention particularly well is one in which the power supply device is equipped with a 3-pole output terminal that combines the positive output terminal, the negative output terminal, and the lighting signal output terminal, and the power supply device and the lighting circuit device are connected using a 3-core cable. With this design, the benefit of not increasing the number of output terminals in the power supply unit becomes even more pronounced, as power supply and identification of the type of lighting circuit can be achieved with a single output terminal. In other words, compared to a power supply unit with a separate terminal for receiving pulse signals for discrimination, resulting in a 4-pole terminal configuration, a 3-pole terminal configuration allows for a thinner outer diameter if the core wire diameter of the cable is kept the same, making it cheaper and lighter. On the other hand, keeping the outer wire diameter of the cable the same allows for a thicker core wire diameter, which suppresses voltage drop and increases the allowable current.

[0012] Furthermore, the power supply device of the present invention comprises a positive output terminal and a negative output terminal connected to a power supply circuit, and a lighting signal output terminal, and is used together with a lighting circuit device which is connected to each of the output terminals via a cable and comprises a lighting circuit that supplies power to a light irradiation device and controls lighting, wherein the lighting circuit device comprises an oscillation circuit that outputs a pulse signal set according to the type of lighting circuit to the positive output terminal or the negative output terminal via the cable, and the power supply device comprises a discrimination circuit that determines the type of lighting circuit based on the received pulse signal, and a switching circuit that switches the conductive destination of the positive output terminal or the negative output terminal to which the pulse signal is input between the power supply circuit and the discrimination circuit. Such a power supply device can achieve the same effects and advantages as the lighting control system of the present invention described above. [Effects of the Invention]

[0013] A lighting control system capable of discriminating a lighting circuit connected to a power supply device with high accuracy can be provided. [Brief Description of the Drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram showing an overall configuration of a light irradiation system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a circuit diagram schematically showing the configuration of the lighting control system of the embodiment. [Figure 3] FIG. 3 is a flowchart explaining the operation of the lighting control system of the embodiment. [Figure 4] FIG. 4 is a block diagram explaining the operation of the lighting control system of the embodiment. [Figure 5] FIG. 5 is a block diagram explaining the operation of the lighting control system of the embodiment. [Figure 6] FIG. 6 is a block diagram explaining the operation of the lighting control system of the embodiment. [Figure 7] FIG. 7 is a circuit diagram schematically showing the configuration of a lighting control system according to another embodiment. [Mode for Carrying Out the Invention]

[0015] Hereinafter, a light irradiation system 200 including a lighting control system 100 according to an embodiment of the present invention will be described with reference to the drawings.

[0016] The lighting control system 100 of the present embodiment is used, for example, in an inspection light irradiation system 200 for performing surface inspection of a workpiece such as a product in a factory or the like. Specifically, as shown in FIG. 1, the light irradiation system 200 includes: a light irradiation device L that irradiates inspection light onto a workpiece; and the lighting control system 100 that supplies power to the light irradiation device L via a power supply cord and controls the light emission mode of the light irradiation device L.

[0017] As shown in FIG. 2, the lighting control system 100 includes a power supply device 1, and a lighting circuit device 2 connected to the power supply device 1 via a cable C, which supplies power to a light irradiation device L to control lighting thereof.

[0018] The light irradiation device L includes, for example, an LED as a light source, and its brightness, light emission time and light emission timing are controlled by power supplied from the lighting control system 100.

[0019] The power supply device 1 includes, in a housing, a power supply circuit 11 provided with a DC power supply, and a signal output circuit 12 that outputs a lighting signal instructing lighting. The housing of the power supply device 1 is provided with a positive output terminal Ot1 that outputs a positive voltage to the outside, a negative output terminal Ot2 that outputs a negative voltage to the outside, and a lighting signal output terminal Ot3 that outputs a control signal instructing lighting to the outside. The positive output terminal Ot1 and the negative output terminal Ot2 are conductively connected to the positive side and the negative side of the power supply circuit 11, respectively. The lighting signal output terminal Ot3 is also conductively connected to the signal output circuit 12.

[0020] The lighting circuit device 2 includes a lighting circuit 21 that receives power supply from the power supply device 1, and supplies power to the light irradiation device L based on a lighting signal received from the power supply device 1 to control lighting thereof. The housing of the lighting circuit device 2 is provided with a positive input terminal It1, a negative input terminal It2, and a lighting signal input terminal It3 corresponding to each output terminal included in the power supply device 1, and each of the input terminals is conductively connected to the lighting circuit 21.

[0021] The positive output terminal Ot1, the negative output terminal Ot2, and the lighting signal output terminal Ot3 included in the power supply device 1 are collectively configured as a 3-pole output terminal OT. The positive input terminal It1, the negative input terminal It2, and the lighting signal input terminal It3 included in the lighting circuit device 2 are also collectively configured as a 3-pole input terminal IT. The power supply device 1 and the lighting circuit device 2 are connected via a 3-core cable C whose both ends are connected to the 3-pole output terminal OT and the 3-pole input terminal IT.

[0022] Furthermore, the control system 100 of this embodiment includes a discrimination mechanism that automatically determines the type of lighting circuit 21 in the lighting circuit device 2 connected to the power supply device 1. Specifically, this discrimination mechanism is configured to include an oscillation circuit 22 provided in the lighting circuit device 2, and a discrimination circuit 13 and a switching circuit 14 provided in the power supply device 1.

[0023] The oscillator circuit 22 is composed of an FPGA or microcontroller and outputs a pulse signal with a pulse width or duty cycle set according to the type of lighting circuit 21. The oscillator circuit 22 is conductively connected to the positive input terminal It1 and the negative input terminal It2, and is powered through the positive input terminal It1 and outputs a pulse signal through the negative input terminal It2. Specifically, the oscillator circuit 22 outputs a pulse signal to the negative output terminal Ot2 of the power supply unit 1 via a 3-core cable C.

[0024] The discrimination circuit 13 is composed of an FPGA and a microcontroller, and receives a pulse signal output from the oscillation circuit 22. Based on the received pulse signal, it determines the type of lighting circuit 21. Specifically, the discrimination circuit 13 stores the duty cycle or pulse width of the pulse signal and the type of lighting circuit 21 in memory beforehand, and determines the type of lighting circuit 21 based on the duty cycle or pulse width of the received pulse signal. The discrimination circuit 13 is connected to the negative output terminal Ot2 in a conductive manner.

[0025] The switching circuit 14 alternately switches the destination of the negative output terminal Ot2, which is the terminal to which the pulse signal output from the lighting circuit device 2 is input, between the power supply circuit 11 and the discrimination circuit 13. The switching circuit 14 is constructed using a switching element such as an FET switch.

[0026] The determination mechanism of this embodiment further includes a charge / discharge circuit 23 and a second switching circuit 24 provided in the lighting circuit device 2.

[0027] The charge / discharge circuit 23 performs charging and discharging and includes a capacitor. This charge / discharge circuit 23 is electrically connected to the positive input terminal It1 and the negative input terminal It2. The charge / discharge circuit 23 is connected to the negative input terminal It2 via the oscillation circuit 22. While the charge / discharge circuit 23 is electrically connected to the power supply circuit 11 via the negative input terminal It2 and the negative output terminal Ot2 (i.e., while both the positive output terminal Ot1 and the negative output terminal Ot2 are electrically connected to the power supply circuit 11 in the power supply unit 1), it charges, and when the destination of the conductivity via the negative input terminal It2 and the negative output terminal Ot2 switches to the discrimination circuit 13, it discharges to the oscillation circuit 22.

[0028] The second switching circuit 24 is configured using a switching element such as an FET switch, and switches between a conductive state and a non-conductive state between the negative input terminal It2 and GND (0V).

[0029] Next, the operation of such a lighting control system 100 will be explained with reference to Figures 3 to 6.

[0030] The operation of this lighting control system 100 starts when the lighting circuit device 2 is connected to the power supply device 1 using a 3-core cable C. At startup, the negative input terminal It2 and GND (0V) are in a non-conductive state in the lighting circuit device 2.

[0031] First, the switching circuit 14 turns on the switching element, making the negative output terminal Ot2 connected to the power supply circuit 11 (step S1). As a result, as shown in Figure 4, the oscillation circuit 22 and the charge / discharge circuit 23 in the lighting circuit device 2 are connected to the power supply circuit 11 of the power supply device 1 via the 3-core cable C. During this time, the oscillation circuit 22 oscillates a pulse signal, and the capacitor in the charge / discharge circuit 23 is charged.

[0032] Next, the switching circuit 14 turns off the switching element and switches the destination of the negative output terminal Ot2 to the discrimination circuit 13 (step S2). As a result, as shown in Figure 5, the oscillation circuit 22 in the lighting circuit device 2 is connected to the discrimination circuit 13 of the power supply device 1 via the 3-core cable C. The oscillation circuit 22 operates using the power generated by the discharge of the charge / discharge circuit 23 and oscillates a pulse signal. During this time, the line connecting the oscillation circuit 22 and the discrimination circuit 13 via the 3-core cable C is in a high-impedance state, and the pulse signal oscillated by the oscillation circuit 22 is input to the discrimination circuit 13.

[0033] Next, the discrimination circuit 13 determines the type of connected lighting circuit 21 (step S3). If the discrimination circuit 13 cannot determine the type of connected lighting circuit 21, the operations of steps S1 and S2 are repeated, and the discrimination circuit 13 tries to determine the type of connected lighting circuit 21 again.

[0034] On the other hand, when the detection circuit 13 determines the type of connected lighting circuit 21, it starts the operation to light up the light irradiator L. Specifically, the switching circuit 14 turns on the switching element to switch and fix the connection destination of the negative output terminal Ot2 to the power supply circuit 11 (step S4), and after a certain period of time has elapsed, the second switching circuit 24 turns on the switching element to switch the negative input terminal It2 and GND (0V) to a conductive state in the lighting circuit device 2 (step S5). As a result, as shown in Figure 6, the lighting circuit 21 of the lighting circuit device 2 operates (step S6), and the light irradiator L is lit according to the lighting signal output from the signal output circuit 12 (step S7).

[0035] According to the lighting control system 100 of this embodiment, an oscillation circuit 22 is provided in the lighting circuit device 2 that outputs a preset pulse signal according to the type of lighting circuit 21, and a discrimination circuit 13 is provided in the power supply device 1 that determines the type of lighting circuit 21 based on the pulse signal output from the oscillation circuit 22. Therefore, by connecting the lighting circuit device 2 to the power supply device 1, the type of lighting circuit 21 can be automatically determined on the power supply device 1 side.

[0036] Furthermore, since the discrimination is based on a digital signal, such as a pulse signal, it is possible to make a more accurate discrimination than if the discrimination were based on an analog signal, such as an analog voltage value.

[0037] Furthermore, since the negative output terminal Ot2 to which the pulse signal is input in the power supply unit 1 is configured to alternately switch between the power supply circuit 11 and the discrimination circuit 13, power supply and discrimination of the type of lighting circuit 21 can be realized with a single output terminal. As a result, the function of discriminating the type of lighting circuit 21 can be added to the power supply unit 1 while maintaining the 3-pole output terminal OT configuration without increasing the number of output terminals. By using a 3-pole output terminal OT configuration, the outer diameter of the cable C can be made thinner if the core wire diameter is kept the same, making it cheaper and lighter compared to a 4-pole terminal configuration. On the other hand, if the outer diameter of the cable C is kept the same, the core wire diameter can be made thicker, which suppresses voltage drop and increases the allowable current.

[0038] However, the present invention is not limited to the embodiments described above. For example, in the above embodiment, the oscillation circuit 22 and the discrimination circuit 13 were connected to each other via the negative output terminal Ot2 and the negative input terminal It2, but the system is not limited to this configuration. In other embodiments of the lighting control system 100, as shown in Figure 7, the oscillation circuit 22 and the discrimination circuit 13 may be connected to each other via the positive output terminal Ot1 and the positive input terminal It1. In this case, the connection destination of the positive output terminal Ot1, which is the terminal to which the pulse signal output from the lighting circuit device 2 is input, is alternately switched between the power supply circuit 11 and the discrimination circuit 13.

[0039] Furthermore, the lighting circuit device 2 and the light irradiation device L may be configured as an integral unit, for example, by providing the lighting circuit device 2 inside the light irradiation device L. Needless to say, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from its spirit. [Explanation of Symbols]

[0040] 200... Light irradiation system L...Light irradiation device 100...Lighting control system 1...Power supply device 11...Power supply circuit 12...Signal output circuit 13...Discrimination circuit 14... Switching Circuit Ot1 ···Positive output terminal Ot2 ·· Negative output terminal Ot3 ···Lighting signal output terminal OT ···3-pole output terminal 2 ···Lighting circuit device 21 ···Lighting circuit 22 ···Oscillator Circuit 23...Charge / discharge circuit 24 ···Second switching circuit It1 ···Plus input terminal It2 ···Minus Input Terminal It3 ···Lighting signal input terminal IT ···3-pole input terminal C ·· Cable

Claims

1. A lighting control system that supplies power to a light irradiation device and controls its light emission mode, A power supply device equipped with a positive output terminal, a negative output terminal, and a lighting signal output terminal connected to the power supply circuit, A lighting circuit device comprising a lighting circuit connected to each of the output terminals via a cable and supplying power to the light irradiation device to control lighting, The system includes a discrimination mechanism for determining the type of the aforementioned lighting circuit, The aforementioned discrimination mechanism The lighting circuit device includes an oscillator that outputs a pulse signal, set according to the type of lighting circuit, to the positive output terminal or the negative output terminal via the cable, The power supply unit is provided with, A discrimination circuit that determines the type of the lighting circuit based on the received pulse signal, A lighting control system comprising a switching circuit that switches the destination of the positive output terminal or the negative output terminal to which the pulse signal is input between the power supply circuit and the discrimination circuit.

2. The aforementioned lighting circuit device includes a charge / discharge circuit that performs charging and discharging, The charge / discharge circuit is charged while the positive output terminal and the negative output terminal are connected to the power supply circuit. The lighting control system according to claim 1, wherein when the conductive destination of the positive output terminal or the negative output terminal switches to the discrimination circuit, discharge is performed from the charge / discharge circuit to the oscillation circuit.

3. When the type of the lighting circuit is determined by the discrimination circuit, The lighting control system according to claim 1 or 2, wherein the switching circuit switches the destination of the positive output terminal or the negative output terminal to which the pulse signal is input to the power supply circuit, and the lighting circuit starts supplying power to the light irradiation device.

4. The lighting control system according to claim 1 or 2, wherein the discrimination circuit determines the type of lighting circuit based on the duty cycle or pulse width of the received pulse signal.

5. The power supply device is equipped with a three-pole output terminal that combines the positive output terminal, the negative output terminal, and the lighting signal output terminal, The lighting control system according to claim 1 or 2, wherein the power supply device and the lighting circuit device are connected using a three-core cable.

6. A power supply device comprising a positive output terminal and a negative output terminal connected to a power supply circuit, and a lighting signal output terminal, and a power supply device used together with a lighting circuit device comprising a lighting circuit connected to each of the output terminals via a cable, which supplies power to a light irradiation device and controls the lighting, The lighting circuit device includes an oscillation circuit that outputs a pulse signal set according to the type of lighting circuit to the positive output terminal or the negative output terminal via the cable, A discrimination circuit that determines the type of the lighting circuit based on the received pulse signal, A power supply device comprising a switching circuit that switches the destination of the positive output terminal or the negative output terminal to which the pulse signal is input between the power supply circuit and the discrimination circuit.

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