JP3824603B2 - Power supply system for LED lighting device - Google Patents

Description

  The present invention relates to a power supply system for an LED lighting apparatus suitable for illumination for various optical inspections, symbol reading, and the like.

  2. Description of the Related Art In recent years, with the improvement of LED performance, LED illumination devices have been frequently used for optical illumination for examining minute abnormalities on the surface of an object or reading symbols such as alignment marks. These LED lighting devices are connected to a power supply device prepared according to necessary current and voltage in order to vary the characteristics, arrangement, number, and the like of the LED elements according to the lighting purpose. Further, even in a single lighting device, when the adjustment range is lowered and the power supply set for the rated use is used as it is, there is a problem that fine adjustment becomes difficult.

  In general, an LED input device and a constant current power supply device are each provided with an electrical input connector of the same dimensional standard and an electrical output connector of the same dimensional standard corresponding to the same in the manufacturing stage. Therefore, it is desirable to check the rating and use state of the LED lighting device to be used, and set the range of the power supply device so as to conform to this. However, this procedure is unexpectedly troublesome, and there is a risk of wasting time and failure due to incorrect range setting.

Conventionally, there has been a technique described in the following patent document as an apparatus for confirming an appropriate combination of such a lighting fixture and an illumination power source after the connection between the two.
JP-A-6-94627

  However, the illumination device described in Patent Document 1 uses a filament-enclosed light bulb such as a halogen lamp as a light source, and first, through a current considerably smaller than the rated value on the power source side, without substantially operating the light bulb. By measuring the resistance value specific to the filament and specifying the light source device, the voltage and current corresponding to this are set. Therefore, in the case of an LED, the resistance value becomes almost zero when a current is passed in the forward direction, so this method cannot be applied.

  In recent years, with the increase in power of LEDs and the improvement in the range and selectivity of the emission wavelength range, a wide variety of LED lighting devices have been developed, especially for inspection of articles, and power is supplied to them. Power supply devices for this purpose have also been designed. Therefore, in order to obtain appropriate lighting, unless an appropriate lighting device is selected and used in combination with an appropriate power supply device (or power supply tap), malfunction or failure may occur.

  The present invention is for an LED lighting device capable of automatically recognizing the type of the lighting device or a desired operating state and supplying power corresponding to the lighting device using an LED when connected to a predetermined power source. It is intended to provide a power system.

  Furthermore, the present invention can easily embody the technical idea of the present invention by installing a simple additional mechanism even if it is an existing LED lighting device, and automatically connect it to a predetermined power source. It is an object of the present invention to provide a power supply system for an LED lighting device that can recognize the model of the lighting device or a desired operating state and perform power supply corresponding to the recognized type.

  As a basic form for solving the above-described problems, the power supply system for an LED lighting device according to the present invention described in claim 1 images a workpiece, which is an imaging object, with an imaging device such as a CCD camera, and performs image processing on the workpiece. By configuring a workpiece imaging system for inspecting scratches generated on the surface of the workpiece or reading symbols such as alignment marks,

An LED energizing circuit including at least one LED, a model discrimination resistor having a resistance value corresponding to the standard or usage characteristics of the LED energizing circuit, and an LED terminal, a resistance terminal, and a common terminal An LED illumination device for irradiating the workpiece with light;

Determine belongs to which range the resistance value of the model determination resistor is predetermined from the voltage value of said resistor terminal, and a model determination unit for outputting a determination signal of the stepwise values depending on the result, the A power supply device having a constant current control unit that sets a maximum allowable current value according to the value of the determination signal and supplies a control current in an arbitrary range below the maximum allowable current value to the LED energization circuit;

  It is characterized by having.

Of course, the present invention is not limited to the work imaging system. In that case, an LED energization circuit including at least one LED, a model discrimination resistor having a resistance value corresponding to the standard or use characteristics of the LED energization circuit , an LED terminal, a resistance terminal, and a common terminal 3 An LED lighting device having a terminal, and a power supply device for supplying power to an LED energization circuit of the LED lighting device, wherein the resistance value of the resistor for model discrimination belongs to a predetermined range. A model discriminating unit that judges from the voltage value of the terminal and outputs a judgment signal of a stepwise value according to the result, and sets the maximum allowable current value according to the value of the judgment signal and the maximum allowable current value What comprises the power supply apparatus provided with the constant current control part which supplies the control current in the following arbitrary ranges to the said LED electricity supply circuit is preferable.

Furthermore, in the power supply system for an LED lighting device according to the third aspect of the present invention, the model determination unit outputs a predetermined determination signal even when the resistance value of the model determination resistor is infinite. .

  On the other hand, as described above, even in a single lighting device, when the adjustment range is lowered and the power supply set for the rated use is used as it is, there is a problem that fine adjustment becomes difficult. .

In order to effectively solve this, a dimming signal receiving unit that receives the dimming signal and a range switching unit that can be switched at least between two states of a normal state and a low power state are further provided, and the value of the received dimming signal The constant current control unit supplies a control current having a value in accordance with the LED energization circuit,

  When the range switching unit is in a normal state, the control current of the maximum allowable current value is supplied to the LED energizing circuit when the value of the received dimming signal is maximum, while the range switching unit is reduced. When in the power state, the control current having a value smaller than the maximum allowable current value is supplied to the LED energizing circuit even when the value of the received dimming signal is maximum. Is preferred.

Even if the adjustment range is lowered, it is particularly preferable if the constant current control unit is configured to increase the adjustment resolution of the control current by the dimming signal accordingly.

  According to a sixth aspect of the present invention, there is provided an LED energization circuit including at least one LED, a model discrimination resistor having a resistance value corresponding to the standard or use characteristics of the LED energization circuit, an LED terminal, and a resistance Power is supplied to an LED lighting device having a terminal and a common terminal, and the range of the resistance value of the model discrimination resistor belonging to a predetermined range is determined from the voltage value of the resistance terminal. A model discriminating unit for determining and outputting a stepwise value determination signal according to the result, and setting a maximum permissible current value according to the value of the determination signal, and an arbitrary range below the maximum permissible current value And a constant current control unit for supplying the control current to the LED energization circuit.

  Since the power supply system for an LED lighting device of the present invention is configured as described above, when a lighting device using an LED is connected to a predetermined power source, the model of the lighting device or a desired operating state is automatically set. Recognizing and providing an excellent effect of being able to supply power corresponding to it.

  The power supply system for an LED lighting device according to the present invention is also an existing LED lighting device, and when it is connected to a predetermined power source via a predetermined adapter element, the model or desired type of the lighting device is automatically selected. The present invention exhibits an excellent effect that it can recognize the operating state of and can supply power corresponding thereto.

  As a result, the power supply system for an LED lighting device according to the present invention can correspond to a plurality of types, for example, about 10 types of LED lighting devices with one type of power source in any of the above-described forms.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. 1 to 7 show a first embodiment according to the basic form of the invention, FIGS. 8 to 10 show a second embodiment according to another form of the invention, and FIGS. 11 to 12 show a third embodiment according to the invention. Respectively.

In the first embodiment shown in FIG. 1, the LED lighting device 1 includes an LED 2, and includes, for example, an LED energization circuit ending with both terminals a and b of a terminal row 3 composed of a power input connector, Alternatively, a model discriminating resistor 4 having a resistance value R corresponding to the usage characteristics is provided. In this case, the model identification resistor 4 is inserted between one end of the energizing circuit, that is, between the anode side (a) of the LED and another terminal c in the terminal row 3 (hereinafter referred to as “resistor terminal c”). However, it can be electrically separated from the energization circuit as in the example described later. In addition, the model discrimination resistor 4 is used as a variable resistor or a tap-switching resistor, and the lighting device 1 equipped with the resistor is used.
It can also be used for switching (light output level range).

  According to the setting of the light output of the lighting device 1, for example, as shown in FIG. 2, the LEDs 2 are connected in series and in parallel as many as necessary in the energizing circuit, and each element is configured to pass a current corresponding to the rated value. be able to. Such a configuration of an energization circuit including a plurality of LEDs can also be adopted in all embodiments described later.

  Further, as shown in FIG. 3, the lighting device 1 is provided with a necessary number of the LED energization circuits as described above according to the setting of the light output and the wavelength, and each circuit has a corresponding model discrimination resistor R1. , R2... Can be connected to each other, and multiplexing or hybridization such as juxtaposition of combinations 3-1, 3-2,. Each LED energizing circuit may have one end (here a side) connected to a common line as shown in the figure, or may be a completely separated circuit. Of course, even if the number of LEDs and the number of LED energization circuits are different, it can be used.

Referring to FIG. 1 again, the power supply device 5 for supplying power to the LED energizing circuit of the LED lighting device 1 is connected to both ends of the LED energizing circuit, in this case, both terminals a and b of the input terminal array 3. A terminal array 6 including, for example, an output connector including a possible pair of power supply terminals a ′ and b ′, which is connected to the power supply terminal b ′ and a constant voltage power supply unit 7 connected to the power supply terminal a ′. The intermediate terminal c ′ of the output terminal row 6 which includes the constant current source 8 thus formed as a main part and can be connected to the resistance terminal c of the input terminal row 3
A model discrimination unit 9 connected to a measurement input terminal connected to (hereinafter referred to as “resistor terminal c ′”) is provided. As a matter of course, this resistance measuring means is connected to both ends of the model discrimination resistor 4 in relation to the power supply units 7 and 8, and accurately measures the resistance value R.

  FIG. 4 shows a lighting device 1a in which a resistor R is connected to the cathode side of LED 2, that is, a terminal c side, and an input / output of a constant current control unit 8 backed up by a constant voltage power supply unit 7. An example of a system configuration in which a power supply device 5a is inserted between a ′ and b ′ so that a model discrimination signal is supplied not only to the constant current control unit 8 but also to the constant voltage power supply unit 7 is shown. It is. Of course, it is of course possible to combine the illumination device 1 described above and the power supply device 5a in this system, or to combine the illumination device 1a in this system and the power supply device 5 described above.

  The model discrimination unit 9 sends a model discrimination and control signal to the constant current control unit 8 (and also to the constant voltage power source unit 7 in the circuit of FIG. 4) according to the measured resistance value R of the model discrimination resistor 4 alone. The constant current control unit 8 controls the power supply circuit of the power supply device 5 so that the control current in an arbitrary range below the maximum allowable current value is applied to the LED energization circuit of the lighting device 1 by the pair of power supply terminals a ′ and Flow through b '. The constant current control unit 8 is further supplied with a dimming signal 10 so that an arbitrary light output level can be obtained. FIG. 5 summarizes the above operation flow.

As another modification of the basic form of the present invention, as shown in FIG. 6, the input terminal row 3 ′ on the lighting device 1 side is a four-terminal type, and the equipped model discrimination resistor 4 includes a third terminal c, Corresponding to this, the output terminal row 6 ′ of the power supply device 5 is also a four-terminal type, and the resistance measurement input of the model discriminating section 9 is the terminal row 6 ′.
The third terminal c ′ and the fourth terminal d ′ are connected to form a measurement circuit for the model discrimination resistor 4 which is electrically completely independent from the LED. Other parts indicated by the same reference numerals as those in FIG. 1 are the same functional elements as those in FIG. 1, and further description thereof is omitted.

  FIG. 7 shows a basic embodiment using an adapter system. The illumination device 1 does not include the model discrimination resistor 4, and the input terminal row 3 ″ is provided with both terminals a and b connected to the LED energization circuit. The configuration of such an illumination device 1 is the same as the conventional one. In the present embodiment, the adapter type relay terminal row 12 is coupled to the input terminal row 3 ″, so that a self-specific function for the power source can be exhibited. In this case, the adapter type relay terminal row 12 is electrically connected to the input terminal row 3 ″ via a relay cable 13 extending between similar terminal structures.

  The relay terminal row 12 is equipped with a model discrimination resistor 4 having a resistance value corresponding to the standard or usage characteristics of the LED energization circuit in the lighting device 1, and both ends of the LED energization circuit, that is, both terminals a and Connected to a pair of relay input / output terminals a ″ and b ″ connectable to the relay cable 13 via the input / output terminals a ′ ″ and b ′ ″ of the relay cable 13 and one end of the equipped model discrimination resistor 4 In this case, the other end of the model discrimination resistor 4 is connected to the relay input / output terminal a ″.

  The power supply device 5 is the same as that shown in FIG. 1, and its output terminal row 6 supplies power to the LED energization circuit of the lighting device 1 via the adapter type relay terminal row 12. 'And b' are connected to the pair of relay input / output terminals a "and b" in the relay terminal row 12, and an intermediate terminal c '(resistance terminal c') is connected to the resistance measuring terminal c ". The operation is similar to that of FIG.

  In the power supply device 5, when the same output terminal row 6 ′ as that of FIG. 6 is used, the resistance measurement terminal c ″ in the adapter type relay terminal row 12 is divided into two, and the model discrimination resistor provided in this is divided. In addition to being connected to both end points, a pair of measurement input terminals c ′ and d ′ in the output terminal row 6 ′ are coupled to these binary terminals.

  FIG. 8 shows a power supply system for an LED lighting device configured as a second embodiment of the present invention.

  The LED lighting device 1 in this system is provided with an LED energization circuit including at least one LED, and has a resistance value corresponding to the standard or usage characteristics of the energization circuit, as in the above-described embodiments. 4 is connected in parallel with the energization circuit.

  The input terminal row 3 ″ in the lighting device 1 has the same two-terminal configuration as shown in FIG. 5, and the output terminal row 6 ″ in the power supply device 5 ′ is connected to the two terminals a and b of the input terminal row 3 ″. It has a corresponding pair of power supply terminals a ′ and b ′.

  The model discriminating unit 9 of the power supply device 5 ′ measures the resistance value of the model discriminating resistor 4 through the pair of power supply terminals a ′ and b ′, and is activated by the connection deviation judging unit 14. It has become. The activated model discrimination unit 9 measures the resistance value of the parallel resistor by applying a measurement voltage having a magnitude that does not affect the operation of the LED energization circuit of the lighting device 1 for a very short time. For example, when the LED is electrically connected and emits light when 2.5 V is applied in the forward direction, even if a low voltage of about 1 V is applied, the resistance value of the LED is a non-conductive resistance value that is almost infinite. If the resistance value R of the model discrimination resistor 4 connected in parallel is about 10 to several tens of kΩ, this value is measured without being affected by the non-conducting resistance value of the LED.

  When the resistance value R of the model discrimination resistor 4 is measured in this way, the application of the measurement voltage by the model discrimination unit 9 and the operation thereof is terminated, and the constant current control unit 8 responds to the resistance value R. A control current in an arbitrary range equal to or less than the set maximum allowable current value of the LED energization circuit is supplied with power supply terminals a ′ and b ′ of the output terminal row 6 ″ and both terminals a of the input terminal row 3 ″ coupled thereto. Supply through b. The disconnection determination unit 14 monitors the power supply / connection state between the LED lighting device 1 and the power supply device 5 ′. When the power supply / connection state is interrupted, the model determination unit 9 is restarted and then connected. The value of the model discrimination resistor related to the lighting device is measured, and an appropriate command for the constant current control unit 8 is generated. FIG. 9 summarizes the above operation flow.

  FIG. 10 shows a modification of the resistor parallel connection type by the adapter method. The illuminating device 1 is a conventional type that does not include the model discrimination resistor 4, and the self-specific function for the power supply can be exhibited by coupling the adapter type relay terminal row 12 ′ to the input terminal row 3 ″. In this case, the adapter type relay terminal row 12 ′ is connected to the output terminal row 6 ″ of the power supply device 5 ′ via a relay cable 13 ′ extending between similar terminal structures.

  The adapter-type relay terminal row 12 ′ is a pair that can be connected to both ends of the LED energization circuit via the input terminal row 3 ″ of the lighting device 1 via the input / output terminals a ′ ″ and b ′ ″ of the relay cable 13. And the relay for input / output terminals a ″ and b ″ and a resistance value corresponding to the standard or usage characteristics of the LED energization circuit is connected to the pair of relay input / output terminals a ″ and the pair of relay input / output terminals a ″. b ″ is a shunt connection.

  The illumination device 5 ′ in this embodiment is the same as that shown in FIG. 6, and the pair of power supply terminals a ′ and b ′ in the output terminal row 6 ″ are connected to the pair of relays in the adapter type relay terminal row described above. It will be readily appreciated that by connecting the input / output terminals a "and b", it operates similarly to that of the embodiment of FIG.

  Next, a third embodiment will be described with reference to FIGS. In addition, the code | symbol in this embodiment shall have no relationship with what was shown by the said FIGS.

  As shown in FIG. 11, the power supply system PSS for the LED lighting device according to this embodiment includes a plurality of LED lighting devices 1A and 1B that illuminate the workpiece W, and power to each of the LED lighting devices 1A and 1B independently. Power supply devices 5A and 5A. And this LED illumination device power supply system PSS images the workpiece W with an imaging device CMR such as a CCD camera from directly above, and inspects scratches or the like generated on the surface of the workpiece W by performing image processing on the workpiece W, It is used as a component of a workpiece imaging system WPS that reads symbols such as alignment marks.

  First, the LED lighting devices 1A and 1B will be specifically described.

  In this example, the first LED illumination device 1A that irradiates light from the periphery side of the workpiece W and the second LED illumination device 1B that irradiates light to the workpiece W from the same direction as the imaging direction via the half mirror HM are used. Yes.

  The first LED illuminating device 1A includes a large number of LEDs 2A arranged in an inward ring shape (for example, an annular shape) along a frame 11A having a through hole in the center, and light emitted from the LEDs 2A is oblique around the workpiece W. The axial line J of the through hole 11aA is arranged so as to coincide with the center of the observation area of the workpiece W so as to be irradiated from the side.

  The second LED illuminating device 1B includes a half mirror HM arranged obliquely right above the through hole, and a plurality of LEDs 2B arranged side by side so as to form a plane on the side of the half mirror HM. The light emitted from each of the LEDs 2B is reflected downward by the half mirror HM, and downwards through the lower surface opening, that is, the imaging direction by the imaging device CMR. It is configured to irradiate from the coaxial direction. In addition, in FIG. 11, the code | symbol 16B has shown the light diffusing plate interposed between the half mirror HM and LED2B.

  Further, as in the first and second embodiments, the LED lighting devices 1A and 1B include, as shown in FIG. 12, a model discrimination having a resistance value corresponding to the standard or usage characteristics of the LED energization circuit including the LEDs 2A and 2B. Resistors 4A and 4B are provided. One end of each of the model determining resistors 4A and 4B is connected to constant voltage sources CPS and CPS provided in power supply devices 5A and 5A, which will be described later, via connectors CN and CN and cables 13A and 13A, respectively, and the other end is The power supply devices 5A and 5A are grounded via measurement fixed resistors 51A and 51A, and form a circuit network independent of the LED energization circuit.

  The imaging device CMR images the workpiece W illuminated by the first LED illumination device 1A and the second LED illumination device 1B. Specifically, the imaging device CMR reflects and scatters the workpiece W and passes through the first LED illumination device 1A. The light that has passed through the lower surface opening, the half mirror HM, and the upper surface opening of the second LED lighting device 1B is captured.

  In the present embodiment, a plurality of power supply devices 5A are provided so as to correspond to the number of LED lighting devices 1A and 1B, and these are accommodated in a single casing CS. Each power supply device 5A is connected to each LED lighting device 1A (1B) via a cable 13A and a connector CN, as shown by a block schematically shown in FIG. And while measuring the resistance value of the model discrimination resistor 4A (4B) provided in the LED lighting device 1A (1B), it is determined to which range the resistance value belongs, and according to the result A model discriminating unit 9A that outputs a stepwise value determination signal S1, a dimming signal receiving unit 17A that receives the dimming signal S2, and the determination signal S1, and a maximum allowable value according to the value of the determination signal S1. A constant current control unit 8A that sets a current value and supplies a control current having a strength proportional to the value of the dimming signal S2 within the maximum allowable current value to the LED energization circuit.

  In the model discrimination unit 9A, the model discrimination resistor 4A (4B) provided in the LED lighting device 1A (1B) and the measurement fixed resistor 51A provided in the power supply device 5A connect the connector CN. The resistance value of the model discrimination resistor 4A (4B) is measured by measuring the potential at the connection point P by utilizing the fact that the constant voltage source CPS and the ground are connected in series. is there. More specifically, a plurality (four in the figure) of comparators 91A in which one input terminal is connected to a plurality of different comparison potentials Vref1 to Vref4 and the connection point is connected to the other input terminal, and these comparators A decoder 92A for decoding the output of 91A, and an output signal of the decoder 92A is formed by a discrete circuit having the determination signal S1. Of course, it goes without saying that an A / D converter, a CPU, or the like may be used. Accordingly, the code (here, 2 bits) which is the value of the determination signal S1 indicates to which range the resistance value of the model discrimination resistor 4A (4B) belongs. In addition, even when the model determination resistor 4A (4B) is not attached, it is determined that the resistance value is infinite.

  The dimming signal accepting unit 17A selectively accepts either the manual dimming signal S2 ′ by the volume VL or the external dimming signal S2 ″ from the outside by the switch SW. The external dimming signal S2 ″. May be analog continuous values or duty-controlled pulse waves.

  The constant current control unit 8A converts (attenuates) the value (voltage value) of the dimming signal S2 into predetermined ratios determined in accordance with the value of the determination signal S1, and outputs the converted signal S3. 81A and an LED drive unit 82A that drives the LED energization circuit with a control current proportional to the value of the conversion signal S3.

  The converter 81A, for example, divides the value of the dimming signal S2 into a plurality of stages by a plurality of resistors connected in series and outputs the divided signal, and the output signal of any one of the voltage divider 811A, The analog switch ASW is selected according to the value of the determination signal S1 and output as the conversion signal S3. The LED driving unit 82A is configured using an operational amplifier 821A and an FET 822A, and its output end is connected to the cathode side of the LED 2A (2B) via the connector CN and the cable 13A.

  Furthermore, in the present embodiment, a range switching unit 18A configured using the changeover switch SW2 is provided on the power supply device 5A side. This range switching unit 18A can be switched between Hi (normal state) and Lo (low power state). When switched to Hi, the value of the received dimming signal S2 is the maximum. The control current having the maximum allowable current value is sometimes supplied to the LED energization circuit.

  On the other hand, when switching to Lo, a control current having a value smaller than the maximum allowable current value is supplied to the LED energizing circuit even when the value of the received dimming signal S2 is maximum. ing. Specifically, when switched to Lo, a dummy resistor 181A is connected in parallel with the model discrimination resistor 4A (4B), and the model discrimination resistor 4A (measured by the model discrimination unit 9A) The resistance value 4B) is apparently small, and the maximum value of the control current is set to a value smaller than the maximum allowable current value.

  Thus, when the first LED illumination device 1A and the second LED illumination device 1B are arranged as in the workpiece imaging system WPS of this embodiment, the second LED illumination device 1B that irradiates light from the coaxial direction with the imaging device CMR includes: The power supply device 5A connected to the first LED illumination device 1A sets the switch to Hi while the second LED illumination device 1B does not require such a high luminous intensity and does not need to exhibit its maximum illumination function. The connected power supply device 5A sets the changeover switch to Lo.

  Therefore, according to the present embodiment, the models of the LED lighting devices 1A and 1B are automatically recognized by the values of the model discrimination resistors 4A and 4B, and the power supply adapted thereto is performed. It is possible to effectively avoid problems such as these. In addition, since it can be realized with a discrete circuit configuration, it can be made inexpensive and highly reliable.

  Moreover, when it is not necessary to use the rated power as in the case of the second LED lighting device 1B, if it is attempted to control this only by the dimming signal S2, there arises a problem that fine adjustment becomes difficult. However, even if the range switching unit 18A is set to Lo and the maximum value of the control current is set to a value smaller than the maximum allowable current value, that is, the adjustment range is lowered, the adjustment resolution of the control current by the dimming signal S2 can be reduced accordingly. Because it is raised, fine adjustment is possible.

  That is, as in the workpiece imaging system WPS, a plurality of LED illumination devices 1A and 1B are required to effectively illuminate the workpiece W, and each of the LED illumination devices 1A and 1B has various kinds of brightness adjustments. Even when use in a mode is required, according to the LED lighting device power supply system PSS of the present embodiment, a sufficient response is possible, and the effect becomes very remarkable.

  Further, even when the model discrimination resistor 4A (4B) is not attached, the resistance value is infinite and the model of the LED lighting devices 1A and 1B is automatically recognized. The manufacturing cost can be reduced by not mounting the model discrimination resistor 4A (4B) to the model. Alternatively, it is possible to recognize a model that has already been shipped before the present invention and does not have the model identification resistor 4A (4B).

  As a modification of the present embodiment, for example, regarding the range switching unit, one provided on the LED illumination device side can be cited. Further, as in the above-described embodiment, not only binary but also three or more values can be switched, or a variable resistor may be used and the like can be switched continuously. Of course, not only the configuration in which the value of the model discrimination resistor is apparently changed, but also a configuration in which a variable amplifier is installed after the dimming signal receiving unit and the gain of the variable amplifier is switched may be used. A configuration may be adopted in which the amplification factor in the LED driving unit is switched. In addition, if it is the structure which changes apparently the value of the model discrimination resistor like the said embodiment, it is suitable at the point which can provide a range switch part in the LED lighting apparatus side easily.

  Moreover, as shown in FIG. 13, you may use this power supply system for LED lighting apparatuses for LED lighting apparatus 1C using power LED which can flow the electric current of 200 mA or more continuously. This LED illuminating device 1C incorporates a power LED 2C, a lens mechanism 15C, and the like in a cylindrical finned casing 11C, and emits light to the outside from the tip surface 14C. Of the three cables 13Ca, 13Cb, 13Cc in the figure, two are for power supply, and one is connected to a model discrimination resistor (not shown). If a constant voltage power source is used in such a way that consumes a large current in this way, the power consumption at the power source internal resistance increases, which is not preferable, but it is of the current control type as in the present invention. The problem can be solved, and the effect becomes remarkable.

  In addition, for example, the dimming signal may be a pulse signal for controlling brightness by a duty ratio. In the embodiment, such a pulse signal can be input as an external dimming signal.

  Of course, if there are many types of LED lighting devices, it goes without saying that the number of switching steps of the maximum allowable current value may be changed accordingly.

It is a diagram showing a first embodiment which is a basic aspect of the present invention. It is a circuit diagram which shows an example in case the LED electricity supply circuit in the said 1st Embodiment has several LED. In the said 1st Embodiment, it is a circuit diagram which shows the modification at the time of multiplexing or hybridizing a LED electricity supply circuit. It is a diagram showing another system configuration example in the first embodiment. It is an operation | movement flowchart in the said 1st Embodiment. It is a diagram which shows the further another modification in the said 1st Embodiment. It is a diagram which shows the modification at the time of attaching the adapter in the said 1st Embodiment. It is a diagram which shows 2nd Embodiment of this invention. It is an operation | movement flowchart of the said 2nd Embodiment. In the said 2nd Embodiment, it is a diagram which shows embodiment at the time of attaching an adapter. It is a whole schematic diagram which shows the workpiece | work imaging system containing the power supply system for LED lighting apparatuses in 3rd Embodiment of this invention. It is a typical block diagram which shows the whole power supply system for LED lighting apparatuses in the said embodiment. It is a longitudinal cross-sectional view which shows the internal structure of the LED lighting apparatus in the modification of this invention.

Explanation of symbols

1, 1A, 1B, 1C ... LED lighting device 2, 2A, 2B, 2C ... LED
3 ... Input terminal row 4, 4A, 4B ... Model discrimination resistor 5, 5A ... Power supply device 6 ... Output terminal row 7 ... Constant voltage controller 8, 8A ... Constant Current control unit 9, 9A ... model discriminating unit 10, S2 ... light control signal 12 ... adapter type terminal array 13, 13A ... relay cable 14 ... disconnection judgment unit

Claims (3)

A workpiece for imaging a workpiece, which is an object to be imaged, by an imaging device such as a CCD camera, and processing the image, thereby inspecting a scratch generated on the surface of the workpiece or reading a symbol such as an alignment mark Comprising an imaging system,
An LED energizing circuit including at least one LED, a model discrimination resistor having a resistance value corresponding to the standard or usage characteristics of the LED energizing circuit, and an LED terminal, a resistance terminal, and a common terminal An LED illumination device for irradiating the workpiece with light;
A model discrimination unit that determines a predetermined range of the resistance value of the model discrimination resistor from the voltage value of the resistance terminal, and outputs a stepwise value determination signal according to the result, and A power supply device having a constant current control unit that sets a maximum allowable current value according to the value of the determination signal and supplies a control current in an arbitrary range below the maximum allowable current value to the LED energization circuit;
A dimming signal receiving unit for receiving the dimming signal;
A range switching unit that can be switched at least to two states, a normal state and a low power state,
The constant current control unit is configured to supply a control current having a value according to the value of the received dimming signal to the LED energization circuit, and
When the range switching unit is in a normal state, the control current of the maximum allowable current value is supplied to the LED energization circuit when the value of the received dimming signal is maximum,
When the range switching unit is in a low power state, a dummy resistor is connected in parallel with the model identification resistor, the resistance value is apparently small, and the value of the received dimming signal is maximum. A control current having a value smaller than the maximum allowable current value is supplied to the LED energization circuit, and the control current adjustment resolution by the dimming signal is increased accordingly. Power supply system for LED lighting device.   The power supply system for an LED lighting device according to claim 1, wherein the model discrimination unit outputs a predetermined judgment signal even when the resistance value of the model discrimination resistor is infinite. A workpiece for imaging a workpiece, which is an object to be imaged, by an imaging device such as a CCD camera, and processing the image, thereby inspecting a scratch generated on the surface of the workpiece or reading a symbol such as an alignment mark Comprising an imaging system,
An LED energizing circuit including at least one LED, a model discrimination resistor having a resistance value corresponding to the standard or usage characteristics of the LED energizing circuit, and an LED terminal, a resistance terminal, and a common terminal Power supply to the LED lighting device,
A model discrimination unit that determines a predetermined range of the resistance value of the model discrimination resistor from the voltage value of the resistance terminal, and outputs a stepwise value determination signal according to the result, and A constant current control unit that sets a maximum allowable current value according to the value of the determination signal and supplies a control current in an arbitrary range below the maximum allowable current value to the LED energization circuit;
A dimming signal receiving unit for receiving the dimming signal;
A range switching unit that can be switched at least to two states, a normal state and a low power state,
The constant current control unit is configured to supply a control current having a value according to the value of the received dimming signal to the LED energization circuit, and
When the range switching unit is in a normal state, the control current of the maximum allowable current value is supplied to the LED energization circuit when the value of the received dimming signal is maximum,
When the range switching unit is in a low power state, a dummy resistor is connected in parallel with the model identification resistor, the resistance value is apparently small, and the value of the received dimming signal is maximum. A control current having a value smaller than the maximum allowable current value is supplied to the LED energization circuit, and the control current adjustment resolution by the dimming signal is increased accordingly. Power supply.