CN108289354A - Light adjusting circuit and potentiometer - Google Patents

Abstract

The invention relates to a dimming circuit and a potentiometer, including: a potentiometer, a resistor, a bidirectional thyristor, a bidirectional trigger diode and a capacitor; the potentiometer includes a resistor body and a tap, the tap is slidably connected to the resistor body, and the tap is connected to the first end of the capacitor; The first anode of the bidirectional thyristor is connected to the first power supply input terminal, the second anode of the bidirectional thyristor is connected to the second power supply input terminal through the load, and the control terminal of the bidirectional thyristor is connected to the tap through the bidirectional trigger diode; the resistance value of the potentiometer varies with the tap The first end of the resistor body slides toward the second end to gradually increase in size, and an insulating layer is provided on the outer surface of the second end of the resistor body. When the tap slides along the surface of the resistor body, the resistance value of the potentiometer increases as the tap slides from the first end to the second end of the resistor body, so that the brightness of the load decreases. When the tap slides to the insulating layer, the potential The resistance value of the device is infinite, so that the current on the bidirectional trigger diode is zero, and the load is completely turned off.

Description

Dimming circuit and potentiometer

technical field

The invention relates to the technical field of dimming, in particular to a dimming circuit and a potentiometer.

Background technique

The traditional potentiometer dimming switch is turned off by a mechanical switch. The traditional dimming switch mainly adopts two ways to turn off, one is to turn off by an external mechanical switch, and the other is to turn off by a potentiometer with a switch. off. The traditional dimmer switch has a complex circuit structure, which leads to high cost. In addition, the large volume is not conducive to installation.

Contents of the invention

Based on this, it is necessary to provide a dimming circuit and a potentiometer.

A dimming circuit, comprising: a potentiometer, a resistor, a bidirectional thyristor, a bidirectional trigger diode and a capacitor;

The potentiometer includes a resistor body and a tap, the tap is slidably connected to the resistor body, the tap is connected to the first end of the capacitor, and the second end of the capacitor is used to input the second power supply through the load terminal connection, the first end of the resistor body is used to connect to the first power supply input terminal through the resistor;

The first anode of the bidirectional thyristor is used to connect to the first power supply input terminal, the second anode of the bidirectional thyristor is used to connect to the second power supply input terminal through the load, and the control of the bidirectional thyristor The terminal is connected to the tap through the bidirectional trigger diode;

The resistance value of the potentiometer is used to gradually increase as the tap slides from the first end to the second end of the resistor body, and an insulating layer is provided on the outer surface of the second end of the resistor body.

In one of the embodiments, the potentiometer includes a carbon diaphragm potentiometer, and the resistor is a carbon diaphragm.

In one of the embodiments, the insulating layer includes insulating varnish.

In one of the embodiments, the insulating layer includes a rubber layer.

In one of the embodiments, a fuse is further included, the resistor is used to connect to the first power input terminal through the fuse, and the first anode of the bidirectional thyristor is used to connect to the first power input terminal through the fuse. Power input connection.

In one embodiment, the thickness of the insulating layer is 1.2mm-2.2mm.

In one embodiment, the insulating layer has a thickness of 1.5 mm.

In one of the embodiments, the load is also included.

In one of the embodiments, the load is an LED.

A potentiometer, comprising: a resistor body and a tap, the tap is slidably connected to the resistor body, the resistance of the potentiometer is used to slide from the first end to the second end of the resistor body with the tap and gradually increasing, the outer surface of the second end of the resistor body is provided with an insulating layer.

When the above dimming circuit and potentiometer slides along the surface of the resistor, the resistance of the potentiometer gradually increases as the tap slides from the first end to the second end of the resistor, so that the brightness of the load gradually decreases. , and when the tap slides to the insulating layer, the resistance of the potentiometer reaches infinity, so that the current on the bidirectional trigger diode is zero, thereby realizing the complete shutdown of the load. By setting an insulating layer at the second end of the resistor body of the potentiometer, the control of the load from dimming down to completely off can be realized, making the dimming circuit simple in structure, small in size, effectively reducing cost, and convenient Features of the installation.

Description of drawings

Fig. 1 is a schematic circuit diagram of a dimming circuit according to an embodiment;

FIG. 2 is a schematic circuit diagram of a dimming circuit in another embodiment;

FIG. 3 is a schematic structural diagram of a carbon diaphragm of a potentiometer according to an embodiment.

Detailed ways

In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the associated drawings. Preferred embodiments of the invention are shown in the accompanying drawings. However, the present invention can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

It should be noted that when an element is referred to as being “disposed on” another element, it may be directly on the other element or there may also be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for purposes of illustration only and are not intended to represent the only embodiments.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terminology used herein in the description of the present invention is only for the purpose of describing specific embodiments, and is not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

For example, a dimming circuit includes: a potentiometer, a resistor, a bidirectional thyristor, a bidirectional trigger diode, and a capacitor; the potentiometer includes a resistor body and a tap, the tap is slidingly connected to the resistor body, and the tap is connected to the The first end of the capacitor is connected, the second end of the capacitor is used to connect to the second power supply input terminal through the load, and the first end of the resistor body is used to connect to the first power supply input terminal through the resistor; The first anode of the bidirectional thyristor is used to connect to the first power input terminal, the second anode of the bidirectional thyristor is used to connect to the second power input terminal through the load, and the control terminal of the bidirectional thyristor The bidirectional trigger diode is connected to the tap; the resistance of the potentiometer is used to gradually increase as the tap slides from the first end to the second end of the resistor body, and the first end of the resistor body The outer surfaces of the two ends are provided with insulating layers.

In the above embodiment, when the tap slides along the surface of the resistor body, the resistance value of the potentiometer gradually increases as the tap slides from the first end of the resistor body to the second end, so that the brightness of the load gradually decreases. When the tap slides to the insulating layer, the resistance value of the potentiometer reaches infinity, so that the current on the bidirectional trigger diode is zero, thereby realizing the complete shutdown of the load. By setting an insulating layer at the second end of the resistor body of the potentiometer, the control of the load from dimming down to completely off can be realized, making the dimming circuit simple in structure, small in size, effectively reducing cost, and convenient Features of the installation.

As shown in FIG. 1 , it is a dimming circuit of an embodiment, including: a potentiometer VR1, a resistor R1, a bidirectional thyristor SCR1, a bidirectional trigger diode D1 and a capacitor C1; the potentiometer VR1 includes a resistor body and a tap, and the The tap is slidingly connected to the resistor body, the tap is connected to the first end of the capacitor C1, the second end of the capacitor C1 is used to connect to the second power input end through the load, and the first end of the resistor body terminal is used to connect to the first power supply input terminal through the resistor R1; the first anode of the bidirectional thyristor SCR1 is used to connect to the first power supply input terminal, and the second anode of the two-way thyristor SCR1 is used to pass through the The load is connected to the input terminal of the second power supply, and the control terminal of the bidirectional thyristor SCR1 is connected to the tap through the bidirectional trigger diode D1.

Please refer to FIG. 1 and FIG. 3, the resistance value of the potentiometer is used to gradually increase as the tap 120 slides from the first end 111 of the resistor body 110 to the second end 112, and the resistance value of the resistor body 110 The outer surface of the second end 112 is provided with an insulating layer 130 . For example, the outer surface of the second end 112 of the resistor 110 is provided with an insulating layer 130 . For example, the tap 120 is movably abutted against the insulating layer 130 . For example, the tap 120 is slidably disposed on the resistor 110 and the insulating layer 130 .

Specifically, the load (not shown in the figure) is a lighting lamp, for example, the load is an LED (Light Emitting Diode, light emitting diode) lamp, for example, the dimming circuit further includes a load, and the load is an LED. In this embodiment, the first power input terminal is the live wire terminal L, and the second power input terminal is the neutral wire terminal A, that is to say, the first end of the resistor body is used to connect to the live wire through the resistor R1, so The second end of the capacitor C1 is used to connect to the neutral line through the load, the first anode of the bidirectional thyristor SCR1 is used to connect to the live line, and the second anode of the bidirectional thyristor SCR1 is used to connect to the neutral line through the load .

In this embodiment, the bidirectional thyristor SCR1 and the bidirectional trigger diode D1 form a dimming circuit of the triac SCR1 , and by changing the conduction angle of the triac SCR1 , the current of the load is changed to realize the brightness adjustment of the load. When the bidirectional thyristor SCR1 is turned on, the load is turned on, and when the bidirectional thyristor SCR1 is turned off, the load is turned off. The trigger circuit of bidirectional thyristor SCR1 is composed of resistor R1, potentiometer VR1, bidirectional trigger diode D1 and capacitor C1. By changing the resistance value of potentiometer VR1, the conduction angle of bidirectional thyristor SCR1 can be changed, and then the brightness of the load can be changed.

Specifically, the tap slides on the resistor body, so that the resistance value of the potentiometer VR1 changes. The tap is electrically connected to the resistor body, and the resistance of the potentiometer VR1 gradually increases as the tap slides from the first end to the second end of the resistor body, that is, when the tap slides to the first end of the resistor body , when the tap is connected to the first end of the resistor body, the resistance value of the potentiometer VR1 reaches the minimum value, and when the tap gradually slides along the first end of the resistor body to the second end, the resistance value of the potentiometer VR1 increases accordingly. When the brightness of the load reaches the minimum, the tap continues to slide towards the end of the second terminal. When the tap slides to the insulating layer, the tap is completely isolated from the resistor body, and the resistance of the potentiometer VR1 The value is infinite at this time, so that the current flowing on the triac D1 is zero, and the bidirectional thyristor SCR1 is cut off, and then the current on the load is zero, and the load is turned off, realizing the complete shutdown of the load.

As shown in Figure 2, when the tap of the potentiometer VR1 slides to the end of the second end of the resistor body, the tap is disconnected from the resistor body of the potentiometer VR1, which is equivalent to the switch K1 in Figure 2 being closed, and the tap and the potentiometer VR1. The other pin is connected to the ground, and the voltage of the capacitor C2 is clamped to 0V to prevent the interference signal from triggering the bidirectional trigger diode D1 and the bidirectional thyristor SCR1 by mistake.

In this embodiment, by setting an insulating layer at the second end of the resistor body of the potentiometer VR1, the control of the load from dimming down to completely off can be realized, so that the structure of the dimming circuit is simple, the volume is small, and it is effective. Reduces costs and features ease of installation.

It is worth mentioning that in each embodiment, the sliding of the tap on the resistor body can be a straight line or a rotation. For example, if the resistor body is a semicircle, when the tap slides on the resistor body, The body rotates, thereby changing the resistance value of the potentiometer VR1.

In order to further reduce the size of the dimming circuit, in one embodiment, the potentiometer VR1 includes a carbon diaphragm potentiometer VR1, and the resistor is a carbon diaphragm. For example, the carbon diaphragm has a horseshoe-shaped structure. In this embodiment, the potentiometer VR1 is a carbon diaphragm potentiometer VR1, and the material of the resistor body of the potentiometer VR1 is a carbon film. For example, the first end of the carbon diaphragm It is used to connect to the first power input terminal through the resistor R1, and the resistance value of the potentiometer VR1 is used to gradually increase as the tap slides from the first end to the second end of the carbon diaphragm, so The outer surface of the second end of the carbon diaphragm is provided with an insulating layer.

In this embodiment, by setting an insulating layer at the second end of the carbon diaphragm, the tap is completely insulated from the carbon diaphragm, so that the resistance value of the potentiometer VR1 reaches infinity. Make the resistance value of the potentiometer VR1 gradually increase as the tap slides from the first end to the second end of the carbon diaphragm, and when the tap slides to the insulating layer at the end of the second end, the resistance value reaches the maximum, so that The brightness of the load can be completely extinguished after gradually decreasing. In this embodiment, the carbon diaphragm potentiometer VR1 has the characteristics of small size and simple structure, which can make the volume of the dimming circuit smaller and make the circuit structure simpler.

In order to realize the insulation isolation between the tap and the resistor body, in one embodiment, the insulating layer includes insulating varnish, for example, the outer surface of the second end of the carbon diaphragm is coated with insulating varnish, for example, the insulating varnish Including polyester imide resin, for example, the material of the insulating varnish includes polyol resin, polyester imide resin, polyurethane, epoxy resin, bismaleimide resin and organic silicon resin. In the example, by coating the outer surface of the second end of the carbon diaphragm with insulating varnish, the second end of the carbon diaphragm can have good insulation performance, and can completely insulate between the tap and the carbon diaphragm, so that the potentiometer VR1 resistance reaches infinity. In addition, the insulating varnish made of polyol resin, polyester imide resin, polyurethane, epoxy resin, bismaleimide resin and silicone resin has good wear resistance, which can make the insulating varnish The tap is still not worn under long-term friction, effectively improving the service life of the potentiometer VR1.

In order to realize insulation isolation between the tap and the resistor body, in one embodiment, the insulating layer includes a rubber layer. For example, the second end of the carbon diaphragm is provided with a rubber body, the rubber layer has good wear resistance and insulation, can well isolate the tap and the carbon diaphragm, and the rubber layer can withstand the long-term friction of the tap No wear and tear, effectively improving the service life of the potentiometer VR1.

In order to make the tap of the potentiometer slide more smoothly and make the potentiometer easier to use, in one embodiment, the thickness of the insulating layer is 1.2 mm to 2.2 mm. It is worth mentioning that the thickness of the insulating layer is too thick. It will easily make the surface of the resistor body not smooth, which is not conducive to the sliding of the tap, and if the thickness of the insulating layer is too thin, it will be easily worn, resulting in the direct connection between the tap and the resistor body at the second end, which cannot fully isolate the tap and the resistor body. Among them, the thickness of the insulating layer is 1.2 mm to 2.2 mm, which can make the surface of the resistor body relatively smooth, which is conducive to the sliding of the tap on the second end of the resistor body. On the other hand, the insulating layer can have better wear resistance , Effectively improve the service life of the potentiometer.

In order to further make the tap of the potentiometer slide more smoothly, make the potentiometer easier to use, and further improve the service life of the potentiometer, in one embodiment, the thickness of the insulating layer is 1.5mm. In this embodiment, the insulation The thickness of the layer is 1.5mm, which can make the height difference between the surface of the resistor body and the insulating layer smaller, making the sliding surface of the tap smoother, which is conducive to the sliding of the tap on the second end of the resistor body. On the other hand, the insulation The layer has a greater thickness, which can make the insulating layer have better wear resistance and effectively improve the service life of the potentiometer.

In order to enable the dimming circuit to disconnect when overloaded, in one embodiment, the dimming circuit further includes a fuse, the resistor R1 is used to connect to the first power input terminal through the fuse, and the bidirectional thyristor SCR1 The first anode is used to connect to the first power input terminal through the fuse. For example, the resistor R1 is used to connect to the live wire through the fuse, and the first anode of the bidirectional thyristor SCR1 is used to connect to the live wire through the fuse, so that when the dimming circuit and the load are overloaded, the fusing The switch is disconnected, which effectively prevents the dimming circuit and the load from being burned due to overload, and improves the safety of the dimming circuit and the load.

In one embodiment, a potentiometer is provided, including: a resistor body and a tap, the tap is slidably connected to the resistor body, and the resistance value of the potentiometer is used to follow the tap at the first position of the resistor body. The end slides toward the second end to gradually increase in size, and the outer surface of the second end of the resistor body is provided with an insulating layer.

In the above-mentioned embodiments, when the tap slides along the surface of the resistor body, the resistance value of the potentiometer gradually increases as the tap slides from the first end of the resistor body to the second end, so that the brightness of the load gradually decreases, while When the tap slides to the insulating layer, the resistance of the potentiometer reaches infinity, so that the current on the bidirectional trigger diode is zero, thereby realizing the complete shutdown of the load. By setting an insulating layer at the second end of the resistor body of the potentiometer, the control of the load from dimming down to completely off can be realized, making the dimming circuit simple in structure, small in size, effectively reducing cost, and convenient Features of the installation.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. a kind of light adjusting circuit, which is characterized in that including：Potentiometer, resistance, bidirectional thyristor, bidirectional trigger diode and electricity Hold；

The potentiometer includes resistive element and tap, and the tap is slidably connected with the resistive element, the tap and the electricity The first end of appearance connects, and the second end of the capacitance is used to connect with second source input terminal by load, the resistive element First end by the resistance with the first power input for being connect；

The first anode of the bidirectional thyristor with first power input for connecting, and the second of the bidirectional thyristor Anode is used to connect with the second source input terminal by the load, and the control terminal of the bidirectional thyristor passes through described pair It is connect to diac with the tap；

The resistance value of the potentiometer is used to slide to second end in the first end of the resistive element with the tap and gradually increase, The outer surface of the second end of the resistive element is provided with insulating layer.

2. light adjusting circuit according to claim 1, which is characterized in that the potentiometer includes carbon film plate potentiometer, described Resistive element is carbon film plate.

3. light adjusting circuit according to claim 1, which is characterized in that the insulating layer includes insulated paint.

4. light adjusting circuit according to claim 1, which is characterized in that the insulating layer includes rubber layer.

5. light adjusting circuit according to claim 1, which is characterized in that further include fuse, the resistance is for passing through institute Fuse is stated to connect with the first power input, the first anode of the bidirectional thyristor be used for by the fuse with it is described First power input connects.

6. light adjusting circuit according to claim 1, which is characterized in that the thickness of the insulating layer is 1.2mm~2.2mm.

7. light adjusting circuit according to claim 6, which is characterized in that the thickness of the insulating layer is 1.5mm.

8. light adjusting circuit according to claim 1, which is characterized in that further include the load.

9. light adjusting circuit according to claim 8, which is characterized in that the load is LED.

10. a kind of potentiometer, which is characterized in that including：Resistive element and tap, the tap are slidably connected with the resistive element, The resistance value of the potentiometer is used to slide to second end in the first end of the resistive element with the tap and gradually increase, described The outer surface of the second end of resistive element is provided with insulating layer.