WO2002037095A1

WO2002037095A1 - Power supply for simple electrophoresis apparatus

Info

Publication number: WO2002037095A1
Application number: PCT/JP2001/009649
Authority: WO
Inventors: Hiromu Ishibashi
Original assignee: Kabushiki Kaisya Advance
Priority date: 2000-11-02
Filing date: 2001-11-02
Publication date: 2002-05-10
Also published as: JP2002139474A; JP3928769B2

Abstract

A power supply for a simple electrophoresis apparatus, comprising a voltage converter for converting the input voltage to an object voltage output and a feedback adjuster for correcting the fluctuation of the object voltage outputted from the voltage converter by adjusting the voltage in a feedback way, whereby a constant electrophoresis output is always produced even if the input voltage fluctuates.

Description

Description Power supply for simple electrophoresis equipment Technical field

The present invention relates to a power supply device of a simple electrophoresis apparatus that can constantly output a constant electric power even when input voltage fluctuates. Conventional technology

Electrophoretic devices that can separate substances in the body according to their molecular weight and visually confirm the separated substances are used all over the world because of their usefulness.Especially, those that are simple and easy to use Are preferred and have become essential laboratory equipment in the art.

By the way, the power situation in the world varies widely, and a wide range of voltages of about 80 V to 200 V is used for commercial power and home power.

In addition, stable power supply is not always available in some countries and regions.

In such a situation, it is necessary to obtain equipment with different specifications in each country, resulting in different electrophoresis abilities, which makes it extremely difficult to perform unified experiments There is. On the other hand, in a situation where information from around the world can be obtained instantaneously due to the spread of the Internet and other sources, information such as research announcements can also be obtained immediately, and research and development competition will intensify. Therefore, there is a need for something that can always carry out the same experimental research regardless of time and place. Summary of the Invention

In view of the above, the present invention provides a voltage conversion device for converting an input voltage to a target voltage output, wherein the voltage output by the voltage conversion device is higher or lower than the target voltage. The electrophoresis that can always obtain a constant electrophoresis output without being affected by the input voltage by combining it with a feedback adjustment device that adjusts the output voltage by feeding that information back to the voltage converter The power supply for the device has been realized.

This makes it possible to perform electrophoresis operations under constant conditions regardless of the type of power supply.

The voltage conversion device and the feedback adjustment device according to the present invention convert, for example, an input DC voltage to a target DC voltage by adjusting a pulse duty, and include a self-excited oscillator such as a multipibrator.

, V_F converter for converting the voltage for adjustment to frequency, switching element such as FET, transistor, coil for obtaining target voltage, inductor such as transformer, diode, and target voltage pulse A DC-DC converter, a switching regulator, and the like having a combination configuration of a capacitor that accumulates and converts DC into DC are exemplified.

According to such a combination configuration, the input voltage is supplied to a DC-DC converter capable of adjusting the output voltage, and is converted into a constant DC voltage. At this time, the DC voltage is monitored and the value is monitored. It is possible to form a constant DC output voltage by adjusting the pulse duty by feed-packing the fluctuation of the output.

In this case, the monitoring may be performed by a digital control element such as a microcomputer, but since a power supply and peripheral elements are required for the monitoring, the monitoring becomes complicated, so that the above-described analog-to-analog method is used. A good configuration is preferred. According to the present invention, as described above, by using a feedback type DC-DC converter, a constant electrophoretic output can always be obtained, but by further changing this, an electrophoretic output suitable for the purpose can be obtained. In some cases, an additional electrophoretic output adjustment device may be added.

The electrophoresis output adjusting device may, for example, take the DC voltage formed by the voltage converter as a maximum output voltage, further input the DC voltage into a DC-DC converter, and perform step-down adjustment so that a desired output voltage is obtained. Is what you do. The output voltage can be adjusted by changing the pulse duty in the pulse oscillator of the DC-DC converter.

This DC_DC converter may be the same as that of the voltage converter, or may be dedicated to step-down. In some cases, a series regulator may be used.

Further, according to the present invention, an overcurrent or an overvoltage may be generated with respect to the fluctuation of the impedance of the gel, the sample, or the like in the electrophoresis tank. Therefore, a protection device may be added to protect the apparatus and the user.

As the protection device, a current monitoring circuit and a voltage monitoring circuit are mainly used, and a device capable of shutting off a circuit against occurrence of overcurrent or overvoltage is used. Among them, the present invention employs a switching regulator. Since the target DC voltage is formed using a self-excited pulse oscillator, the electrophoretic output can be stopped simply by stopping the oscillation operation of the pulse oscillator. A protective device that does not require any means and is easy to handle can be formed. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing the configuration of the first exemplary embodiment of the present invention. FIG. 2 is a circuit diagram showing a first part of the second embodiment of the present invention. FIG. 3 is a circuit diagram showing a second part of the second embodiment of the present invention. FIG. 4 is a circuit diagram showing a third part of the second embodiment of the present invention.

Example

FIG. 1 is a block diagram showing a configuration of a power supply device of a simple electrophoresis apparatus according to a first embodiment of the present invention.

In the figure, 1 is a rectifier circuit, and an existing rectifier circuit consisting of a diode, a diode bridge, and a capacitor is used.If the power supply is DC, the rectifier circuit 1 becomes unnecessary. _Q

Reference numeral 2 denotes a DC-DC conversion circuit, and reference numeral 3 denotes a constant voltage control circuit. For the DC_DC conversion circuit 2 and the constant voltage control circuit 3, for example, a self-excited or separately-excited switching regulator composed of a combination of a pulse oscillator, a step-up transformer, and a diode capacitor is used. This switching regulator has a DC-DC converter, a pulse oscillator, and a V_F converter that varies the pulse width and pulse interval of the oscillation pulse from this pulse oscillator based on the output of the DC-DC converter. Circuit.

Therefore, in such a switching regulator, the output voltage is monitored, and the output pulse width or pulse interval of the pulse oscillator is adjusted according to the magnitude of the output voltage. The voltage can be maintained at a constant value.

The constant voltage control circuit 3 includes, for example, an AD converter, a one-chip It is also possible to configure by a combination of a microcomputer and the like. In this case, the pulse output from the on-chip microcomputer may be replaced with the oscillation pulse of the self-excited oscillator of the DC-DC conversion circuit.

Reference numeral 4 denotes a protection circuit, which is a circuit that detects an output voltage and an output current and outputs a signal at a predetermined value or more. May be stopped or the electrical connection of the migration output may be temporarily cut off.

Reference numeral 5 denotes a migration output adjusting circuit for further adjusting the output of the constant voltage control circuit 3 by stepping down a user to obtain a voltage necessary for a user's experiment.

Next, the operation of the apparatus shown in FIG. 1 will be described.

When the power input to the input terminal AC is AC, it is rectified by the rectifier circuit 1 and converted to a substantial DC DC.

This DC is supplied to an inductor component such as a transformer or a coil based on the oscillation pulse of a self-excited oscillator by a DC-DC converter circuit 2 to drive the DC intermittently. A new direct current is obtained by rectifying and storing the electromotive force generated based on the current flowing through the element.

As described above, the DC-DC conversion circuit 2 and the constant voltage control circuit 3 can be configured by a switching regulator circuit. In this case, the output voltage is controlled by the pulse width and pulse width of the oscillation pulse of the oscillator. In some cases, the output voltage is determined by the interval ratio (duty) or in the input voltage. In this embodiment, the output voltage is varied by adjusting the pulse duty.

In the switching regulator, when the output voltage of the DC-DC converter 2 fluctuates, the amount of the fluctuation is fed back to the DC-DC converter 2 to change the pulse duty of the self-excited oscillator.

This change is, for example, when the fluctuations are high When the voltage is adjusted to increase or decrease the pulse width and the fluctuation is low, the opposite is true. As a result, even if the input voltage fluctuates, a predetermined constant voltage that is intended is always stably obtained.

The DC voltage corrected to the target voltage as described above is input to the protection circuit 4 and output from the output terminal OUT.

The protection circuit 4 stops the output, for example, when an overcurrent or an overvoltage occurs.

Stopping this output not only directly cuts off the electrical connection, but also operates to stop the oscillation of the oscillator of the DC-DC conversion circuit 2.

In this apparatus, a constant electrophoretic electric output is obtained as the output of the constant voltage control circuit 3. However, when this is further variably used, an electrophoretic output adjusting circuit 5 may be added. In this case, the voltage can be adjusted by adjusting the pulse width and interval of the pulse oscillator as in the case of a combination of a control element such as an on-chip microcomputer and a switching regulator, and the connection with the protection circuit 4 is good. However, a series regulator may be used when the variable range is narrow.

If the migration output adjusting circuit 5 uses a switching regulator, the protection circuit 4 may stop the oscillation of the self-excited oscillator constituting the switching regulator.

2 to 4 show a second embodiment of the present invention.

Note that the reference numerals in the circuit are those that are indispensable for the explanation of the circuit operation, and the configuration and operation of the other elements are apparent to those skilled in the art. Also, it is clear that the present device can be configured with circuit elements other than the illustrated circuit elements. Also, FIGS. 2 to 4 are originally one drawing, but are divided for convenience of description. Therefore In each of the drawings, terminals denoted by the same reference numerals are connected to each other.

In FIG. 2, reference numeral 10 denotes a rectifier circuit, which includes a diode bridge, a capacitor, and a transformer, and converts an AC voltage into a DC voltage. '

Reference numeral 11 denotes a DC-DC conversion circuit, which has a transformer 110 composed of a combination of four coils (111, 111, 111, 114). If the coil 111 is the primary side, the others 112, 113, 114 form the secondary side.

The DC-DC converter circuit 11 further includes an oscillator circuit 115, which has a switching element 115b and an oscillation section 115a that changes the oscillation mode according to the input voltage of the input terminal L1. The excitation current flowing in the primary coil 1 1 of 0 is switched on and off, and the electromotive force obtained by switching is stored and converted to DC. Secondary coil 1 13, Diode 1 16, Capacitor 1 1 7 Contains.

To change the oscillation mode of the oscillation unit means to change the pulse width, the pulse interval, or the duty thereof. For the oscillation circuit 115, for example, an existing chip chip device (HIP166, manufactured by Matsushita Electric Industrial Co., Ltd.) is suitably used.

12 A and 12 B constitute a feedback control signal forming section, and include a voltage dividing resistor 1 19, a photodiode 1 118, a transistor 1 22, a constant voltage diode 1 2 3 and 2 Secondary coil 1 1 2, Diode 1 16 a, Capacitor 1 1 7 a, Transistor 1 2 0, Capacitor 1 2 1, Phototransistor 1 1 8 b, Constant voltage diode 1 2 4, Other It is composed of a combination of these elements.

The photo diode 118a and the phototransistor 118b form a photobra. Photo bra 1 1 8 In this configuration, the phototransistor 118b is turned on and off depending on whether light is emitted from the gate 118a.

The DC-DC conversion circuit 11 and the feedback control signal forming sections 12 A and 12 B constitute the DC-DC conversion circuit 2 and the constant voltage control circuit 3 shown in FIG. 1, and the terminals A 1 and A 2 A constant voltage is obtained.

Reference numeral 13 denotes a power supply for the control circuit, which receives the voltage across the capacitor 11 b in the feedback control signal forming section 12 B and converts this voltage into a smoothing circuit having a choke coil. It is processed and output to the control circuit 15. Terminals Bl and B2 are output terminals.

Reference numeral 15 shown in FIG. 3 indicates a control circuit, which includes an integrated type or a plurality of packaged parts such as a microcomputer, a memory, and other output driver chips, and peripheral elements thereof. The output voltages B 1 and B 2 from the control circuit power supply 13 are supplied to the control circuit 15, and control signals necessary for driving the swimming output adjustment circuit and the protection circuit are formed. The control circuit 15 is also provided with a voltage selection button so that a user can select a desired voltage.

The control circuit 15 is provided with a terminal C 2 to which a signal output when a voltage or a current output from the protection circuit to the electrophoresis apparatus becomes a certain value or more is provided. When the input becomes low level, for example, the control circuit 15 cuts off the output to the terminal C1 and turns off the swimming output adjustment circuit 14 shown in FIG. Further, the control circuit 15 includes terminals C3 to C6 for outputting a signal voltage necessary for driving a current and voltage control unit described later. CS is a control signal generated by the user's voltage selection, and a corresponding voltage is output from the terminal C 1 to the migration output adjustment circuit 14 in accordance with the control signal, and the output voltage is adjusted. .

In FIG. 4, reference numeral 14 denotes an electrophoresis output adjustment circuit. It consists of a combination of a transistor 201, a switching FET 202, a diode, a capacitor 204, and a choke coil to form a so-called step-down switching regulator.

Reference numeral 161 denotes a current control unit that detects the occurrence of an overcurrent and stops the operation of the voltage adjustment unit according to the content of the overcurrent.

Reference numeral 162 denotes a voltage control unit that detects the occurrence of overvoltage and stops the operation of the voltage adjustment unit according to the content of the detection.

In the current controller 161, reference numeral 205 denotes a transistor, and reference numeral 206 denotes a photopower blur composed of a combination of a photodiode and a phototransistor.

In the voltage adjuster 162, reference numeral 207 denotes a photodiode, and reference numeral 208 denotes a phototransistor. A photopower blur is formed by a combination of these. 209 is a transistor.

Similarly, the photodiode 300 and the phototransistor 301 form a photocoupler, the photodiode 302 and the phototransistor 303 form a photodiode, and the photodiode 304 The phototransistor 305 and the phototransistor 305 form a photoforce blur.

In addition, AC in Fig. 2 is a commercial power supply connection terminal, and V in Fig. 4 is a DC voltage supply terminal, which is mainly connected to the output terminal B1.

o 1 and o 2 are electrophoresis output terminals, which are connected to the electrodes in the electrophoresis tank.

Hereinafter, the operation of the apparatus shown in FIGS. 2 to 4 will be described in detail.

Commercial AC power is input from AC in Fig. 2 and is converted to DC voltage by a rectifier circuit 10 composed of a combination of a surge absorber, a transformer, a diode bridge with full-wave rectified output, and a capacitor.

This voltage is applied to the primary coil 1 1 1 of the transformer 110, the oscillation circuit 1 Supplied to 15 to drive the oscillation circuit 1 15 to oscillate. The oscillating circuit 115 starts oscillating, intermittently energizes the exciting current flowing to the primary coil 111, and generates induced electromotive force in the secondary coils 112, 113, 114.

The voltage induced in each of the secondary coils is: Diode 1 16, Other Diodes 1 16a, 1 16 b, Capacitor 1 17 and Other Capacitors 1 17 a, 1 17 b And a DC voltage is formed.

The furnace pressure accumulated in the capacitor 117 turns the transistor 122 on and off based on the level of the divided voltage of the voltage dividing resistor 119 based on the constant voltage diode 123.

When the transistor 122 is turned on, current flows to the photodiode 118a, and the phototransistor 118b is turned on.

When the phototransistor 1 18b turns on, the DC voltage accumulated in the capacitor 1 17a raises the voltage at the input terminal L 1 of the oscillation circuit 1 15 via the capacitor 1 21 The oscillation circuit 115 changes the oscillation duty (for example, to increase the pulse interval) based on this voltage, further changes the excitation current flowing through the primary coil 111, and changes the secondary current. The voltage obtained by the coil 113 and the voltage between the terminals of the capacitor 117 storing the voltage are reduced.

Based on the voltage relationship between the voltage dividing resistor 1 19 and the constant voltage diode 1 23, the transistor 122 is turned off by stopping the base current, and the current flowing through the photodiode 1 18a is reduced. It turns off, and the phototransistor 118b also turns off.

In this state, the voltage between the terminals of the capacitor 117 is kept constant. The input terminal L1 of the oscillator circuit 115 drops with time after the voltage is held by the capacitor 121. When the voltage drops, the voltage at the input terminal L1 drops, and the oscillation duty of the oscillator circuit 115 is adjusted. The voltage value stored in the capacitor 117 is increased.

Turns on when the voltage between the terminals of the capacitor 1 17 becomes higher than the voltage dividing ratio of the voltage dividing resistor 1 19 and the constant voltage value of the constant voltage diode 1 23, turns on the photo transistor 1 18 b, and oscillates. Increase the voltage value of the input terminal L1 of the circuit 115 again, and adjust the oscillation duty of the oscillation circuit 115 to reduce the voltage between the terminals of the capacitor 117.

In this way, feedback control is performed via the secondary coil 113 to keep the voltage between the terminals of the capacitor 117 constant.

When the input voltage increases over time, the voltage supplied to the primary coil 111 increases, and the voltage across the capacitor 117 also increases, as described above. Turns on, and a current flows through the phototransistor 118b.

When the phototransistor 1 18b is turned on, the potential of the input terminal L 1 is induced through the secondary coil 1 1 2 via the capacitor 1 2 1 based on the voltage induced in the secondary coil 1 1 2. Rises, the oscillation duty of the oscillator circuit 115 is adjusted, the voltage between the terminals of the capacitor 117 is reduced, and based on the relationship between the voltage dividing ratio of the voltage dividing resistor 119 and the constant voltage diode 123. To keep the constant voltage value.

More specifically, when the input voltage decreases, the voltage supplied to the primary coil 111 decreases, so that the voltage between the terminals of the capacitor 117 also decreases.

Adjustment of the oscillating circuit 1 15 oscillation caused by the discharge of the capacitor 1 2 1 causes the voltage between the terminals stored in the capacitor 1 17 to increase, and the voltage ratio between the terminal and the voltage dividing resistor 1 19 becomes constant. When the voltage exceeds the constant voltage based on the relationship with the voltage diode 123, the transistor 122 turns on, and the phototransistor 118b also turns on.

When the phototransistor 1 18 b turns on, the secondary coil 1 1 2 The accumulated voltage of the capacitor 1 17a, which has accumulated the induced electromotive force, is supplied to the input terminal L1 of the oscillation circuit 115 through the capacitor 121, and the oscillation output based on this voltage is output to the oscillation circuit 1. Step 15 is performed, and the voltage between the terminals of the capacitor 117 is kept constant.

If an excessive voltage is generated in each secondary coil, the constant voltage diode 124 is turned on, the transistor 120 is turned on, and the input terminal L 1 of the oscillator circuit 115 is turned on. Perform protective operation such as reducing the input voltage and stopping the oscillator circuit 115.

The induced voltage generated in the secondary coil 114 is converted to direct current and supplied to the subsequent control circuit and the like.

The constant voltages (terminals A 1 and A 2) obtained via the feedback voltage control unit 12 are connected to the electrophoresis output adjustment circuit color 14 by the electrophoresis electrical output based on the control of the control circuit 15 at terminals o 1 and o 1. o Form into 2.

In this case, the migration output adjustment circuit 14 switches the transistor FET 201 with a pulse output from the control circuit and switches the switching FET 202 to reduce the voltage based on the pulse duty. The obtained voltage is stored in the capacitor 204 and supplied as a migration output.

203 is a terminal connected to a heat sink for releasing heat from the switching transistor.

The control circuit 15 outputs a signal having a magnitude corresponding to the voltage value set by the user from the terminal C1 and introduces the signal into the migration output control circuit 14. As a result, the circuit 14 outputs a voltage set by the user. As an example, if the maximum voltage output from the terminals A 1 and A 2 is set to 200 V, the user can set it to 120 V, 100 V., 80 V Etc. can be selected.

This allows power to be supplied to various commercial power sources used worldwide. It becomes possible to apply a gas migration device.

16 1 is a current limiting circuit, and when the impedance of the electrophoresis gel connected to the output terminals o 1 and 0 2 decreases and excessive current flows, the transistor 205 turns on and the photo 0 6 turns on.

When a high-level voltage is supplied to the transistor 400 from the terminal C3 of the control circuit 15 and the transistor is on, that is, when the current limiting circuit is set to be operable beforehand, When the photovoltaic brush 206 is turned on as described above, the potential at the terminal C 2 changes to a single level. In this manner, when the potential of the terminal C2 of the control circuit 15 decreases, the control circuit 15 stops supplying the output to the terminal C1 and the transistor 20 of the migration output adjustment circuit 14 Setting 2 to off stops the switching operation of the circuit.

Next, when an excessive voltage is supplied while the desired output voltage is operating, the voltage control circuit 162 is driven.

That is, C 6 is selected from the output terminals C 4 of the control circuit corresponding to the voltage specified in advance, and one of them, for example, C 4 is connected. When the photodiode 300 is turned on, the phototransistor 301 is turned on, where the resistor 21 connected via the phototransistor 301 is connected to the resistor 2 at the base of the transistor 209. 1 2 sets the partial pressure ratio.

When the photodiode 302 is turned on, the phototransistor 303 is turned on, where the resistance 2 11 b connected through the phototransistor 303 is at the base of the S transistor 209. The voltage division ratio is set by the resistor 2 1 2.

When the photo diode 304 is turned on, the photo transistor 305 is turned on, where the resistance connected via the photo transistor 305 is the resistance at the base of the transistor 209. 2 1 2 Sets the partial pressure ratio.

Turns on when the base voltage of transistor 209 exceeds the emitter voltage of transistor 209 connected to constant voltage diode 210, turns on photodiode 207 and turns on the photodiode. The transistor 208 is turned on, and the voltage level of the input terminal C2 of the control circuit goes low. As a result, the control circuit 15 cuts off the output to the terminal C 1, stops the supply of the pulse to the transistor 201, and stops the operation of the migration output adjustment circuit color 14.

The allowable values of the voltages at the output terminals 0 1 and o 2 of the voltage limiting circuit 16 2 are set by the combination of ON and OFF of the output terminals C 4 to C 6 of the control circuit 15. The invention's effect

As described above, in the present invention, the use of the self-regulating constant voltage means prevents the fluctuation of the electrophoretic electric output due to the fluctuation of the input voltage, thereby forming a stable electrophoretic electric output, and the overcurrent. This has made it possible to realize a power supply device for an electrophoresis apparatus that can sufficiently protect against overvoltage.

Claims

The scope of the claims

1. A voltage conversion device that converts an input voltage to a target voltage output, and a feedback adjustment device that adjusts in a feedback manner to correct the change when the target voltage output by the voltage converter fluctuates. A power supply device for a simple electrophoresis apparatus, comprising: ,

2. The power supply device for a simple electrophoresis device according to claim 1, wherein the voltage conversion device and the feedback adjustment device are configured by a switching regulator.

3. The power supply device for a simple electrophoresis device according to claim 1, further comprising a migration output adjustment device that further adjusts the feedback-adjusted voltage conversion device output to form a desired electrophoresis output voltage.

4. The power supply device for a simple electrophoresis device according to claim 1, further comprising a protection circuit for stopping the operation of the voltage conversion device when the output of the migration output adjustment device exceeds a predetermined value.

5. The power supply device for a simple electrophoretic device according to claim 3, further comprising a protection circuit for stopping the operation of the electrophoretic output adjusting device when the output of the electrophoretic output adjusting device exceeds a predetermined value.