TWI601351B - Applicable to a variety of supply voltage control circuit protector - Google Patents

Description

Controllable circuit protector for multiple supply voltages

The present invention is a controllable circuit protector, and more particularly a controllable circuit protector that can be applied to a variety of supply voltages.

Referring to FIG. 9, the general fuse device 40 includes an input terminal I/P4, an output terminal O/P4, a control terminal C4, a first temperature fuse 41, a second temperature fuse 42 and a heating resistor R4. The first temperature fuse 41 is connected in series with the second temperature fuse 42 , and the series connection of the first temperature fuse 41 and the second temperature fuse 42 is further electrically connected to one end of the heating resistor R4 . The free end of the first temperature fuse 41 forms the input end I/P4, the free end of the second temperature fuse 42 forms the output end O/P4, and the free end of the heating resistor R4 forms the control end C4.

When the fuse device 40 is used, the input terminal I/P4 is electrically connected to a power source 50, and the output terminal O/P4 is electrically connected to a load 60, and the control terminal C4 is electrically connected to a switch through a switch SW4. Ground GND.

The switch SW4 is controlled to be disconnected or connected according to the state of the load 60. When the load 60 is in an abnormal state, the switch SW4 can be connected to connect the free end of the heating resistor R4 to the ground GND. At this time, the power supplied from the power source 50 starts to energize the heating resistor R4 to increase the temperature of the heating resistor R4, causing the first temperature fuse 41 or the second temperature fuse 42 to be melted.

The rate of increase of the temperature of the heating resistor R4 is determined by the heating power of the heating resistor R4 itself, and when the temperature of the heating resistor R4 exceeds the melting temperature of the first temperature fuse 41 or the second temperature fuse 42, the first The temperature fuse 41 or the second temperature fuse 42 will be melted. Wherein, the heating power of the heating resistor R4 is calculated according to the following formula:

;

Where P is the heating power of the heating resistor R4, V is the voltage supplied by the power source 50, and R is the resistance value of the heating resistor R4.

When it is detected that the load 60 is abnormal in state, the first temperature fuse 41 or the second temperature fuse 42 needs to be melted in a specific time to protect and protect the load 60. Therefore, when the resistance value R of the heating resistor R4 is a fixed value, the melting time of the first temperature fuse 41 or the second temperature fuse 42 is related to the heating power P of the heating resistor R4, when the heating resistor R4 When the heating power P is higher, the shorter the melting time of the first temperature fuse 41 or the second temperature fuse 42 is negatively correlated. The heating power P of the heating resistor R4 is positively correlated with the square of the voltage V supplied from the power source 50. Therefore, the melting time of the first temperature fuse 41 or the second temperature fuse 42 is negatively correlated with the square of the voltage V supplied by the power source 50.

That is to say, the larger the voltage V supplied by the power source 50, the shorter the melting time of the first temperature fuse 41 or the second temperature fuse 42 is.

However, when the manufacturer of the fuse device 40 manufactures the fuse device 40, the same heating resistor R4 is used, that is, the resistance value R of the heating resistor R4 is a fixed value. Therefore, the fuse device 40 is only applicable to the power source 50 having a specific voltage value or more. When the voltage V of the power source 50 is less than the specific voltage value, it means that when the load 60 is abnormal, the switch SW4 is turned on, and the heating power P of the heating resistor R4 is insufficient, so that the first temperature fuse 41 or the second temperature is caused. The fuse 42 has a long melting time or even a failure to fuse, and the fuse 60 is not immediately melted to protect the load 60, causing the load 60 to be damaged and damaged.

For example, if the manufacturer's fuse device 40 is applied to the 220V power supply 50, it means that when the load 60 state is abnormal, the switch SW4 is turned on, and the voltage V of the power source 50 is 220V, so that the heating resistor R4 The heat is generated so that the first temperature fuse 41 or the second temperature fuse 42 can be immediately melted. However, when the fuse device 40 is applied to the power supply 50 of 110V, it means that when the switch SW4 is turned on, the voltage V of the power supply 50 is 110V, so that the heating power of the heating resistor R4 is lowered, and the first temperature fuse 41 or the The melting time of the second temperature fuse 42 is increased, resulting in failure to instantaneously melt or even melt, causing the load 60 to be abnormally damaged.

Therefore, the manufacturer's fuse device 40 can only be applied to the 220V power supply 50, and cannot be applied to the 110V power supply 50. If the fuse device 40 is to be used in the 110V power supply 50, the manufacturer must redesign the fuse device 40. The fuse element 40 is remanufactured by the resistance value of the heating resistor R4. For the manufacturer of the fuse device 40, a dedicated fuse device 40 has been developed for each of the power sources of different voltages, and the manufacturing cost is relatively increased. The current power supply equipment is operated at full voltage (90~260V) and cannot meet the current requirements. Therefore, the existing fuse device 40 cannot be used in AC alternating current, and can only be used under DC direct current of 30V, so there is a need to further Improvement.

In view of the fact that the above-mentioned general fuse device can only be applied to a power source having a specific voltage after the completion of the fabrication, the power source for different voltages needs to develop different fuse devices separately, which causes a disadvantage of increasing the cost of the manufacturer, and the present invention provides a power supply voltage suitable for various power supply voltages. The controllable circuit protector is suitable for power supplies of many different voltages. The controllable circuit protector suitable for a plurality of power supply voltages comprises: a first low temperature metal fuse; a second low temperature metal fuse connected in series with the first low temperature metal fuse; wherein the first low temperature metal fuse The free end of the wire forms an input end, and the free end of the second low temperature metal fuse forms an output end; a first heating unit, one end of which is electrically connected to the first low temperature metal fuse and the second low temperature a series connection of metal fuses, and the free end of the first heating unit forms a control end; at least one second heating unit is connected in parallel with the first heating unit.

The low temperature metal fuse device suitable for a plurality of power supply voltages is used to electrically connect the input terminal to a power source, electrically connect the output terminal to a load, and electrically connect the control terminal to a ground through a switch. end.

When the load abnormality is detected, the switch is controlled to be turned on, so that the control terminal is electrically connected to the ground. At this time, the first heating unit and the at least one second heating unit connected in parallel form a circuit with the power source and the first low temperature metal fuse, and according to the magnitude of the voltage supplied by the power source, all or part of the at least a second heating unit is melted to form an open circuit, or the at least one second heating unit is not melted, so that the first heating unit is connected in parallel with the unmelted portion of the at least one second heating unit, thereby changing An equivalent resistance value of the first heating unit and the unmelted portion of the at least one second heating unit. Therefore, when the total heating power of the first heating unit and the unmelted portion of the at least one second heating unit is calculated according to the formula, the total heating power is followed by the unmelted portion of the at least one second heating unit. The quantity changes. Therefore, when the voltage of the power source changes, the equivalent resistance value changes, so that the total heating power does not change drastically due to the voltage change of the power source, thereby allowing the first low temperature metal fuse or the second Low temperature metal fuses can be instantly melted.

Since the number of the at least one second heating unit is determined by the voltage of the power source, the total heating power is slowed by the magnitude of the power supply voltage, thereby making the controllable circuit protector applicable. For a variety of different voltage power supplies, Jane province manufacturers' production costs.

The technical means adopted by the present invention for achieving the intended purpose are further explained below in conjunction with the drawings and preferred embodiments of the present invention.

Referring to Figure 1, the present invention is a controllable circuit protector 10 suitable for use with a variety of supply voltages for use with a variety of different voltage sources. The controllable circuit protector 10 for a plurality of power supply voltages includes a first low temperature metal fuse 11, a second low temperature metal fuse 12, a first heating unit R1 and at least one second heating unit 131~13n.

The second low temperature metal fuse 12 is connected in series with the first low temperature metal fuse 11, and the free end of the first low temperature metal fuse 11 forms an input terminal I/P1, and the second low temperature metal fuse 12 The free end forms an output O/P1. In the preferred embodiment, the first low temperature metal fuse 11 and the second low temperature metal fuse 12 are low temperature alloy metal fuses.

One end of the first heating unit R1 is electrically connected to the series connection of the first low temperature metal fuse 11 and the second low temperature metal fuse 12, and the free end of the first heating unit R1 forms a control end C1 . In the preferred embodiment, the first heating unit R1 is a heating resistor or a heater.

The at least one second heating unit 131~13n is respectively connected in parallel with the first heating unit R1. In the preferred embodiment, each of the at least one second heating units 131~13n includes a second heating element R131~R13n and a fuse 141~14n, and the second heating element R131~R13n is connected to the fuse. 141~14n in series. In the preferred embodiment, the second heating elements R131 R R13n are a heating resistor or a heater. In the preferred embodiment, the current interrupting capacity of the fuses 141~14n of each of the at least one second heating units 131-131n, that is, the current withstand current is less than the first low temperature metal fuse 11 or the second low temperature metal. Fuse 12. Further, the current interruption capacities of the fuses 141 to 14n of the at least one second heating unit 131 to 131n are different from each other.

The controllable circuit protector 10 for a plurality of power supply voltages is used to electrically connect the input terminal I/P1 to a power source 20, and electrically connect the output terminal O/P1 to a load 30, and The control terminal C1 of the first heating unit R1 is connected to a ground terminal GND through a switch electrical connection SW1.

The first low temperature metal fuse 11 and the second low temperature metal fuse 12 are directly connected between the power source 20 and the load 30. Therefore, when the voltage supplied by the power source 20 is abnormal, the first low temperature metal fuse 11 or the second low temperature metal fuse 12 directly melts the current generated by the abnormal voltage provided by the power source 20 to protect the load 30. Not affected by the abnormal voltage provided by the power source 20. Therefore, the first low temperature metal fuse 11 and the second low temperature metal fuse 12 also have the same function as a general simple fuse.

When the load 30 is detected as abnormal, regardless of whether the voltage supplied by the power source 20 is abnormal, a control command is generated to turn on the switch SW1, and the control terminal C1 is electrically connected to the ground GND. At this time, the first heating unit R1 and the at least one second heating unit 131~13n connected in parallel form a loop with the power source 20 and the first low temperature metal fuse 11, and the voltage is supplied according to the power source 20. The fuses 141~14n in all or part of the at least one second heating unit 131~13n may be broken to form an open circuit, or all the at least one second heating unit 131~13n may not be melted. The first heating unit R1 is connected in parallel with the unmelted portion of the at least one second heating unit 131~13n, thereby changing the first heating unit R1 and the unmelted portion of the at least one second heating unit 131~ The equivalent resistance value of 13n. Therefore, when the total heating power of the first heating unit R1 and the second heating unit 131~13n is calculated according to the formula, since the total heating power is calculated according to the equivalent resistance value and the voltage of the power source 20, the total The heating power changes with the number of the second heating units 131 to 13n which are not melted. Therefore, when the voltage of the power source 20 changes, the equivalent resistance value changes, so that the total heating power does not change drastically due to the voltage change of the power source 20, thereby allowing the first low temperature metal fuse 11 or The second low temperature metal fuse 12 can be immediately melted.

In addition, the current interruption capacity of the fuses 141 14 14n of each of the at least one second heating units 131 ～ 131 n is smaller than the first low temperature metal fuse 11 or the second low temperature metal fuse 12 . Even if the first low temperature metal fuse 11 or the second low temperature metal fuse 12 has not been melted due to the abnormality of the voltage supplied from the power source 20, when the switch SW1 is turned on, each of the at least one second heating unit 131 Some of the ~131n fuses 141~14n will be melted first. After the first heating unit R1 and the second heating units 13 are turned on to increase the temperature, the first low temperature metal fuse 11 or the second low temperature metal fuse 12 is the first heating unit R1 and the The heat provided by the second heating unit 13 is melted to protect the load 30.

That is, according to the design of the present invention, when the load 30 is abnormally turned on, the switch SW1 is turned on, and the fuses 141~14n in the at least one second heating unit 131~13n are first determined according to the voltage of the power source 20. The quantity, thereby changing the equivalent resistance of the first heating unit R1 connected in parallel and the second heating units 131~13n of the unmelted portion, further changing the heating power to avoid the first low temperature metal fuse 11 or The melting time of the second low temperature metal fuse 12 varies with the voltage value of the power source 20.

In summary, since the number of the at least one second heating units 131~13n is turned on after the switch SW1 is turned on, the number of the at least one second heating units 131~13n that is melted is determined according to the voltage of the power source 20. The equivalent resistance value of the first heating unit R1 and the unmelted portion of the at least one second heating unit 131~13n is changed according to the voltage of the power source 20, so the total heating power varies with the voltage of the power source 20. The amplitude will be slowed down, which in turn makes the controllable circuit protector 10 suitable for a variety of different voltage power supplies, simplifying the manufacturing cost of the manufacturer.

For example, as shown in FIG. 2 and FIG. 3, the number of the second heating units 131~13n is one, the resistance value of the first heating unit R1 is 910 Ω, and the second of the second heating units 131. The heating element R131 is 300 Ω.

As shown in FIG. 2, when the plurality of power supply voltage controllable circuit protectors 10 are applicable to an environment in which the voltage value of the power source 20 is 110V, and when the load 30 abnormally turns on the switch SW1, the second heating unit The fuse 141 in 131 does not melt, so the equivalent resistance and total heating power are calculated according to the following two formulas:

;

;

The equivalent resistance of the first heating unit R1 in parallel with the second heating unit 131 is 225.61 Ω, and the total heating power is calculated to be 53.63 W according to the formula.

As shown in FIG. 3, when the controllable circuit protector 10 of the plurality of power supply voltages is applicable to an environment where the voltage value of the power source 20 is 220V, and when the load 30 is abnormal, the switch SW1 is turned on, the second heating. The fuse 141 in the unit 131 is melted, so the equivalent resistance and the total heating power are calculated according to the following two formulas:

The equivalent resistance of the first heating unit R1 and the second heating unit 131 is closed because the second heating unit 131 has been melted, so the resistance value of the first heating unit R1 is 910 Ω, and the total heating is calculated according to the formula. The power is 53.18W.

Therefore, when the control circuit protector 10 of the plurality of power supply voltages is applied to different power supply 20 voltage environments, the total heating power can be maintained close to the power supply 20 without the drastic change of the power supply 20 voltage. The melting time of the first low temperature metal fuse 11 or the second low temperature metal fuse 12 can be stabilized and immediately melted to protect the load 30.

For another example, referring to FIG. 4, FIG. 5 and FIG. 6, the number of the second heating units 131~13n is two, and the resistance value of the first heating unit R1 is 1050 Ω, and the second heating The second heating element R131 in the unit 131 is 1000 Ω, and the second heating unit R132 in the other second heating unit 132 is 480 Ω.

As shown in FIG. 4, when the plurality of power supply voltage controllable circuit protectors 10 are applicable to an environment in which the voltage value of the power source 20 is 110V, and when the load 30 abnormally turns on the switch SW1, the second heating is performed. The fuses 141 and 142 in the units 131 and 132 are not melted, so the equivalent resistance and the total heating power are calculated according to the following two formulas:

;

;

The equivalent resistance of the first heating unit R1 in parallel with the second heating units 131, 132 is 247.78 Ω, and the total heating power is calculated to be 48.83 W according to the formula.

As shown in FIG. 5, when the plurality of power supply voltage controllable circuit protectors 10 are applicable to an environment where the power source 20 has a voltage value of 165 V, and when the load 30 abnormally causes the switch SW1 to be turned on, the other second The fuse 142 in the heating unit 132 is melted, so the equivalent resistance and the total heating power are calculated according to the following two formulas:

The equivalent resistance of the first heating unit R1 in parallel with the second heating unit 131 is melted by the other second heating unit 132, so that the first heating unit R1 and the second heating unit 131 are connected in parallel The effective resistance is 512.19 Ω, and the total heating power is calculated to be 53.15 W according to the formula.

As shown in FIG. 6, when the control circuit protector 10 of the plurality of power supply voltages is applicable to an environment where the voltage value of the power source 20 is 220V, and when the load 30 is abnormal, the switch SW1 is turned on, the second The fuses 141 and 142 in the heating units 131 and 132 are all melted, so the equivalent resistance and the total heating power are calculated according to the following two formulas:

The equivalent resistance of the first heating unit R1 in parallel with the second heating unit 131 is melted due to the second heating units 131 and 132, so the resistance value of the first heating unit R1 is 1050 Ω, and according to the formula The total heating power was calculated to be 46.09 W.

It can be seen that when the controllable circuit protectors 10 of the plurality of power supply voltages are applied to different power supply 20 voltage environments, the total heating power does not change drastically.

Referring to FIG. 7 and FIG. 8 , when the number of the second heating units 131 ～ 13 n is five, respectively, it can be applied to six different power source 20 input voltages respectively, and according to FIG. 2, in six types. The breaking time of the first low temperature metal fuse 11 or the second low temperature metal fuse 12 can be stably maintained at about 5 to 7 seconds under different input voltages, and according to FIG. 3, in six different ways. The total heating power is stably maintained at about 45 to 54 W under the input voltage. Therefore, the controllable circuit protector for a plurality of power supply voltages of the present invention can be applied to a plurality of different power supply 20 input voltages, and both of them can be used in the load. When the abnormality is 30, the first low temperature metal fuse 11 or the second low temperature metal fuse 12 is immediately melted to protect the load 30.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the present invention. A person skilled in the art can make some modifications or modifications to equivalent embodiments by using the above-disclosed technical contents without departing from the technical scope of the present invention, but without departing from the technical solution of the present invention, according to the present invention. Technical Substantials Any simple modifications, equivalent changes and modifications made to the above embodiments are still within the scope of the technical solutions of the present invention.

10‧‧‧Controllable circuit protector

11‧‧‧First low temperature metal fuse

12‧‧‧Second low temperature metal fuse

131~13n‧‧‧second heating unit

141~14n‧‧‧Fuse

20‧‧‧Power supply

30‧‧‧load

40‧‧‧Fuse device

41‧‧‧First temperature fuse

42‧‧‧Second temperature fuse

50‧‧‧Power supply

60‧‧‧ load

1 is a schematic view of a device in accordance with a preferred embodiment of the present invention. 2 and 3 are schematic views showing the use of the preferred embodiment of the present invention. 4, 5 and 6 are schematic views showing another use of the preferred embodiment of the present invention. Figure 7 is a graph showing the relationship between the input voltage and the fuse blowing time in accordance with a preferred embodiment of the present invention. Figure 8 is a graph showing the relationship between input voltage and resistance heating power in accordance with a preferred embodiment of the present invention. Figure 9 is a schematic circuit diagram of a general fuse device.

10‧‧‧Controllable circuit protector

11‧‧‧First low temperature metal fuse

12‧‧‧Second low temperature metal fuse

131~13n‧‧‧second heating unit

141~14n‧‧‧Fuse

20‧‧‧Power supply

30‧‧‧load

Claims (7)

A controllable circuit protector suitable for a plurality of power supply voltages, comprising: a first low temperature metal fuse; a second low temperature metal fuse connected in series with the first low temperature metal fuse; wherein the first low temperature metal The free end of the fuse forms an input end, and the free end of the second low temperature metal fuse forms an output end; a first heating unit, one end of which is electrically connected to the first low temperature metal fuse and the second a series connection of the low temperature metal fuse, and the free end of the first heating unit forms a control end; at least one second heating unit is connected in parallel with the first heating unit; wherein each of the at least one second heating unit The current interrupting capacity of the fuse is less than the current interrupting capacity of the first low temperature metal fuse or the second low temperature metal fuse. A controllable circuit protector suitable for a plurality of supply voltages as recited in claim 1, wherein the first low temperature metal fuse and the second low temperature metal fuse are alloy metal fuses. A controllable circuit protector suitable for a plurality of power supply voltages as claimed in claim 1, wherein the first heating unit is a heating resistor or a heater. The controllable circuit protector as claimed in any one of claims 1 to 3, wherein each of the at least one second heating unit comprises: a second heating element; and a fuse, and And in series with the second heating element. A controllable circuit protector as claimed in claim 4, which is suitable for a plurality of supply voltages, wherein the second heating element is a heating resistor or a heater. The controllable circuit protector applicable to a plurality of power supply voltages according to any one of claims 1 to 3, wherein the current interruption capacities of the fuses of each of the at least one second heating unit are different from each other. A controllable circuit protector suitable for a plurality of power supply voltages as claimed in claim 4, wherein the current interrupt capacities of the fuses of each of the at least one second heating unit are different from each other.