JP3292229B2 - Power supply for sign light - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply for a sign lamp for boosting an AC voltage from an inverter by a transformer, applying the voltage to a sign lamp such as a neon tube or an argon tube, and lighting the sign lamp.

[0002]

2. Description of the Related Art Conventionally, a power supply device which boosts commercial power with a neon transformer and applies the boosted power to a sign light has been mainly used. On the other hand, recently, a power supply device, which uses an inverter to boost electric power having a frequency higher than the commercial electric power using a transformer and applies the electric power to a sign light, has been widely used because of its small size and light weight.

As shown in FIG. 8A, this inverter type power supply for a sign lamp receives commercial power from a commercial power supply 11 through input terminals 12a and 12b to a rectifier circuit 13, and outputs a rectified output from the inverter 14 to a commercial AC power supply. The power is converted to AC power of a frequency higher than the frequency of the power, for example, about 20 KHz, and the AC output of the inverter 14 is boosted by the leakage transformer 15, output between the output terminals 16a and 16b, and connected between the output terminals 16a and 16b. Sign light 1
7 and the sign lamp 17 is turned on.

In this inverter system, since the frequency of the AC power boosted by the transformer 15 is high, the transformer 15 can be significantly reduced in size and weight. However, as shown in FIG. 9A, the sign light 17 is usually mounted on an iron support panel plate 18 via a sign light support 19, and the sign light 17 is provided.
Is supported by a insulator 22 mounted on the support panel plate 18. The support panel plate 18 is grounded, between the distribution line 21, the sign light 17 and the support panel plate 18, between the sign light 17 and the distribution line 21, between the sign light and the sign light 17, between the distribution line 21 and the distribution line. The stray capacitance 23 between the output terminals 16a and 16b is not negligible with respect to the frequency of the inverter output AC power. For example, as shown in FIG.
The AC current reaching the central part of the sign lamp 17 considerably leaks due to the floating capacitance 23. As the distance from the output terminals 16a and 16b increases, the brightness of the sign lamp 17 decreases and the brightness unevenness increases. In some cases, the sign lamp 17 may not be turned on. In addition, due to the influence of the capacitance between adjacent sign lights, particularly in a complicated sign light display device, sign lights connected to different sign light transformers may be arranged close to each other. Interference may occur between these sign lamps, for example, such that the extinguished sign lamps are turned on under the influence of adjacent lighting sign lamps. In particular, in the case of a neon signboard used outdoors, when the distribution line 21 is long, or in rainy weather, the neon tube at the center is turned off or interference occurs between the neon tubes.

[0005] For this reason, by shortening the length of the distribution line 21 as much as possible, it is possible to light four neon tubes (total length of 6 m) and six argon tubes (total length of 9 m), equivalent to 9 kV commercial frequency lighting. Was just obtained.

[0006]

When the commercial power is directly boosted by a transformer, the voltage is raised to 15 kV, and eight neon tubes (12 m in total tube length) or 12 argon tubes (1 in total tube length).
8m) is often used, but in the inverter system, the load wiring was made as short as possible, and only lighting of 9 kV corresponding to direct boosting of commercial power was finally achieved.

In order to solve this problem, conventionally,
It has been proposed to (1) increase the distance between wires or the distance between the sign lamp and the support panel plate, and (2) lower the AC power frequency. However, in the method (1), the interval needs to be greatly increased, and the demand for a small, complicated and high-density display is increasing.
The sign light supports and insulators used for commercial frequency lighting cannot be used, and increasing the space between the sign light and the support panel board requires a large occupied space, requires a lot of work, and looks good. not good. The method (2) is, for example, 20k
When the frequency is set to half of Hz, that is, about 10 kHz, the frequency band becomes an audio frequency band, causing a problem of a noise source, and a transformer becomes large.

In order to facilitate the insulation of the secondary winding of the transformer from the ground, in a foreign country, as shown in FIG. 8B, the transformer 15 is provided with two secondary windings 25a and 25b. One end of each of the secondary windings 25a and 25b is connected, the connection point 26 is grounded, and the other end of each of the secondary windings 25a and 25b is connected to the output terminals 16a and 16b.
In this case as well, the voltage between the output terminals 16a and 16b and the grounded connection point 26 becomes E _0/2, respectively, but this is added at the connection point 26, that is, the terminal 16
a, 16b between is E _0, Looking for the influence of the stray capacitance, the secondary winding 25a of a real lighting state, 25b
The absolute value of the potential with respect to the ground of FIG. 8A, FIG. 8B and FIG.
As shown in the figure, the middle point or the connection point 26 is at zero potential, whereas it is positively and negatively at E _0/2 , that is, at the same level in absolute value, and its maximum value is E _0/2 . Moreover, the secondary winding 25
Since the connection point 26 between the a and 25b is completely grounded, the impedance between the secondary windings 25a and 25b and the magnetic core of the transformer 15 becomes zero, and the leakage current tends to further increase.

[0009] From such a point, Japanese Patent Application No. 7-292751.
A power supply device as shown in FIG. 10A was proposed in the issue "Signal Light Power Supply Device". In FIG. 10A, parts corresponding to those in FIG. 8A are denoted by the same reference numerals.
Are provided with two secondary windings 25a and 25b, the ends of the same polarity of the secondary windings 25a and 25b are connected to each other, and a connection point 31 is connected to a common terminal 32, and the secondary winding 25
The other ends of the terminals a and 25b are connected to the output terminals 16a and 16b. The sign lamp 17 is connected between the common terminal 32 and the output terminals 16a and 16b.

According to this configuration, the output terminals 16a, 16b
The voltage between each of the common terminal 32 are both E _0/2, and the
Since the potentials of the output terminals 16a and 16b have opposite polarities, the voltage between the terminals 16a and 16b becomes 0, and the secondary windings 25a and 25b generate ground potentials in the opposite direction with the respective midpoints being zero potentials. , the absolute value of this for the ground potential is maximum as shown in FIG. 10B, a half of that of the case of FIG. 8C, i.e. becomes E _0/4, the magnitude of the stray capacitance 23 is a same as the conventional However, the leakage current is reduced by half compared to the conventional case. Therefore, many sign lamps can be connected, and a device equivalent to a conventional 15 KV commercial frequency lighting power supply device can be obtained. However, the output wiring increases by one.

For example, even in the case of a neon signboard, it is not always necessary to connect many sign lights between the transformers in view of the display shape and size, so that the wiring length including the sign light is not so long. There is. Also, there is no danger of rain on sign lights such as channel letters,
Further, since the diffusion panel is provided behind, unevenness of brightness is not conspicuous.

In some cases, a power supply for a sign lamp capable of obtaining a higher luminance by flowing a larger secondary current is required. As described above, there are various demands for the power supply for a sign lamp, and different power supplies for a sign lamp are conventionally used in accordance with the respective demands. An object of the present invention is to provide a power supply for a sign lamp that can be used for various requests.

[0013]

Means for Solving the Problems] transformer alternating current high voltage from a commercial frequency is applied two provided by this invention,
One end of each of the two secondary windings is connected to each other, and the connection point and each other end are respectively connected to the output terminal, so that the primary windings of both transformers can switch the connection polarity by a polarity switch. Connected in parallel.

The output voltages of the two secondary windings can be added, subtracted, and connected in parallel by changing the polarity of the polarity switch and connecting the three output terminals.

[0015]

DETAILED DESCRIPTION OF THE INVENTION Figure 1A shows a technique <br/> related to this invention, FIG. 6A, are given the same reference numerals corresponding to those in FIG. 10A. In this embodiment, the transformer 15 is provided with two secondary windings 25a and 25b having the same number of turns.
Both ends of 5a, 25b are output terminals 16a, 16b, 16
c, 16d.

With such a configuration, as shown in FIG. 1B, the output terminals 16b and 16c to which one ends of the secondary windings 25a and 25b having different polarities are connected are connected, and the other ends are connected. Sign light 1 between output terminals 16a and 16d
Connecting 7, between the output terminals 16a, 16d, each secondary winding 25a, a voltage E ₀ to the output voltage E _0/2 is added and 25b is output. Therefore, a large driving voltage is required, the wiring is short, and it is suitable for use in a place where rain does not occur. In this case, the secondary windings 25a and 25
b, the absolute value of the ground voltage is E as shown in FIG.
_0/2 .

As shown in FIG. 1C, the secondary windings 25a, 25
b output terminals 16b and 16 to which one ends of the same polarity are connected.
d between the output terminals 16a and 16b and the output terminal 1
6b, respectively when connecting same sign lamp 17 between 16c, become power supply and the same state shown in FIG. 10A, the output terminal 16a, 16c between the secondary winding 25a, the output voltages of 25b E _0/2 There are subtracted from each other, 0V, and the secondary winding 25a, the absolute value of the ground potential of 25b is the maximum value as shown in FIG. 1F becomes E _0/4. Therefore, more sign lights can be connected than before, and if the wiring is relatively long,
Suitable for applications that do not like uneven brightness.

As shown in FIG. 1D, the secondary windings 25a and 25a
The output terminals to which the same polarity ends of b are connected are connected to each other, that is, the output terminals 16a and 16c, 16b and 16d are respectively connected, and the sign lamp 17 is connected between the output terminals 16a and 16b. The secondary winding 25a of the case, the absolute value of the ground potential of 25b becomes E _0/4 at the maximum, as shown in FIG. 1G. In this case, the output voltages of the secondary windings 25a and 25b are connected in parallel and output. The drive voltage is not so high, and the number of connected sign lights is halved. It is suitable for lighting high-intensity sign lights.

[0019] Figure 2A shows another technique associated with this invention, are given the same reference numerals when corresponding to FIG. In this embodiment, two transformers 15a and 15b are provided as transformers to which the output of the inverter 14 is supplied, and both ends of the secondary windings 25a and 25b of the transformers 15a and 15b are output terminals 16a, 16b and 16c. , 16d.
According to this configuration, as shown in FIGS.
By connecting the output terminals 16a and 16d in the same manner as B, C and D, the output voltages of the secondary windings 25a and 25b can be respectively added, subtracted and connected in parallel.

[0020] shows an embodiment of this invention in FIG. 3A, are given the same reference numerals to portions corresponding to FIG. 2. In this embodiment, 15a is used as a transformer to which the output of the inverter 14 is supplied.
And 15b, the primary winding 3 of the transformer 15a.
8a and the primary winding 38b of the transformer 15b are connected in parallel by a polarity switch 39 capable of switching the connection polarity. In this example, the movable contacts 39a and 39b of the changeover switch 39 are connected to both ends of the primary winding 38b, and the fixed contacts 39c and 39 to which the movable contact 39a is switched are connected.
d is connected to fixed contacts 39f and 39e to which the movable contact 39b is switched and connected. When the movable contact 39a is connected to the fixed contact 39c, the movable contact 39b is linked so as to be connected to the fixed contact 39e. , Fixed contact 39
The connection point between c and 39f and the connection point between the fixed contacts 39d and 39e are connected to both ends of the primary winding 38a and to both output terminals of the inverter 14.

One ends of the secondary windings 25a and 25b having different output polarities are connected to each other.
b, and the other ends of the secondary windings 25a and 25b are connected to output terminals 16a and 16c, respectively. In this configuration, as shown in FIG. 3B, the movable contacts 39a and 39b of the changeover switch 39 are connected to the fixed contacts 39c and 39e, respectively, and the sign lamp 17 is connected between the output terminals 16a and 16b.
Are connected, the secondary winding 2 is connected to the output terminals 16a and 16c.
The outputs of 5a and 25b are added and output.

As shown in FIG. 3C, the changeover switch 39
The movable contacts 39a, 39b of the fixed contact 39d,
39f, and the same number of sine lamps 17 are connected between the output terminals 16a and 16b and between the output terminals 16b and 16c, respectively.
The output voltage of 25b is subtracted and added and output. As shown in FIG. 3D, the changeover switch 39 is set to the connection state shown in FIG. 3C, the output terminals 16a and 16c are connected, and the output terminal 16a
When the sign lamp 17 is connected between the output terminal 16b and
Both outputs of the secondary windings 25a and 25b are connected in parallel.

The rectifier circuit 13 and the inverter 14 in FIG. 1A
FIG. 4 shows an example of the above. That is, the rectifier circuit 13 is a full-wave rectifier circuit, and the inverter 14 has the capacitors 34 and 35 connected in series and the switching elements 36 and 37 connected in series between the output terminals of the rectifier circuit 14.
Connection point between capacitors 34 and 35 and switching element 3
The primary winding 38 of the transformer 15 is connected between the connection points 6 and 37, and the driving circuit 39 controls the switching elements 36 and
37 are turned on and off alternately. That is, the inverter 14 is configured as a so-called half bridge circuit.

Further, in this example, an independent leakage magnetic circuit is formed for each of the secondary windings 25a and 25b. For example, FIG.
As shown in the figure, one long side 41a of the square-shaped magnetic core 41
The primary winding 38 is located in the upper central part, and the secondary winding 25 is located on both sides thereof.
a and 25b are wound respectively, and the leakage cores 42a and 42b are projected from the other long side 41b so as to approach the long side 41a between the primary winding 38 and the secondary windings 25a and 25b, respectively. I have. Thus, the secondary windings 25a, 25
An independent leakage magnetic circuit 43a, 43b is formed for each 5b.

If the leakage magnetic circuits of the secondary windings 25a and 25b are the same, the number of the sign lights 17 connected to the terminal 32 and the terminals 16a and 16b is the same, that is, the load circuit is the same. However, due to the stray capacitance of these load circuits and the variation in the discharge starting voltage of the sign lamp, only one side will discharge first, and the current limiting drooping characteristics of the leakage transformer will cause the load circuit to discharge. If the voltage between the terminals drops, the other side will be below the firing voltage and will not light up,
It lights up on one side.

However, as shown in FIG.
Since the leakage magnetic circuits 43a and 43b are provided independently for the a and 25b, even if the sign lamp on one side discharges first,
Only the output characteristics of the lit secondary winding are in the current limiting droop state, the output voltage of the other secondary winding is not affected, and the sign lamp is lit to the other side with a delay. FIG. 5B shows a structure in which the core of the transformer 15 has a core shape. Further, as shown in FIGS. 2A and 3A, when the two transformers 15a and 15b are provided, the outer shape of the transformer is formed in a core shape. An example is shown in FIG. 5C.

When two transformers 15a and 15b are provided as shown in FIGS. 2A and 3A, two inverters 14a and 14b are used as shown in FIG. , 14b may be supplied to transformers 15a, 15b, respectively. FIG. 6B shows a case where two rectifier circuits 13a and 13b are used. The power supply device of the present invention is not limited to the case of receiving commercial AC power, but may be configured to receive DC power and supply it to the inverter. In some cases, the output of the inverter may be received. That is, an inverter may be provided outside and may be far away, and a plurality of transformers 15 or 15a and 15b may be driven by one inverter. Further, the inverter is not limited to the separately excited type but may be a self-excited type. FIG. 7 shows a specific example in which parts corresponding to those in FIG. A capacitor 51 is connected between both ends of the primary winding 38. Both ends of the primary winding 38 are connected to one end on the output side of the rectifier circuit 13 through switching elements 36 and 37, and a middle point of the primary winding 38 is a choke 52.
And the other end of the tertiary winding of the transformer 15, that is, the oscillation (feedback) winding 53, is connected to the control electrodes of the switching elements 36 and 37. A bias circuit 54 is connected between both ends of the switching element 36, 3.
7, a bias is applied to each of the control electrodes 7 to form an oscillation circuit, and the oscillation output thereof, that is, AC power having a frequency higher than the commercial frequency from the inverter is boosted by the transformer 15 and the secondary winding 25a, 25b provides a high-voltage AC output.

[0028]

As described above, FIG. 1 and FIG.
According to the technology , AC power having a frequency higher than the commercial frequency is supplied to the transformer, and the transformer can be configured to be small and lightweight.
In addition, by selecting the connection of the output terminal, the secondary winding output can be selected from addition output, subtraction output and parallel connection output, depending on the size, shape, construction site condition, etc. of the sign light device. Output can be. In the case of the addition output or the parallel connection output, only two wires are required and the construction is easy. In the case of the subtraction output, the number of wirings is three. However, brightness unevenness is small, the number of connected sign lights can be increased, and the sign lights can be arranged close to each other. If the output is connected in parallel, a large output current can be obtained, and it can be used for sign display with high luminance.

[0029] In this invention requires the output terminals at three, by providing a polarity switching on the primary side, and FIG. 1
The same effect as the technique shown in FIG. 2 can be obtained, and for example, addition output and subtraction output can be performed by switching at a low voltage portion. According to the present invention, it is not necessary to prepare power supplies corresponding to various requests for the sign light device.

[Brief description of the drawings]

[1] A diagram showing a technique related to the invention this is, B or C is a diagram showing the various use conditions, E or G is used state B
9A to 9C are diagrams showing potential distributions (absolute values) of the secondary winding to ground (absolute values).

[2] A is a diagram illustrating another technique related to the invention of this, B
Or D is a diagram showing the various use conditions.

[3] A is a diagram showing an embodiment of the invention of this, B or D is a diagram showing the various use conditions.

[4] shows to view a specific example of a separately excited inverter.

FIGS. 5A and 5B are diagrams showing a structural example of a transformer 15 in FIG. 1A, and C is a diagram showing a structural example of the transformers 15a and 15b in FIGS. 2A and 3A.

FIG. 6 is a diagram showing an example applied to the present invention and providing an inverter for each transformer.

[7] shows to view a specific example of a self-excited inverter.

8A is a diagram illustrating a conventional inverter-type two-wire output power supply device, FIG. 8B is a diagram illustrating a conventional inverter-type three-wire output power supply device, and FIG. 8C is a diagram illustrating a ground potential distribution of a secondary winding of the device of FIG. FIG.

FIG. 9A is a diagram showing an example of a relationship between a sign light supported by a support panel plate and a distribution line, and FIG. 9B is a diagram showing a state of brightness of the installed sign light.

FIG. 10A is a diagram showing the power supply device for a sign lamp proposed earlier, and FIG. 10B is a distribution diagram of the secondary winding of the secondary winding with respect to ground (absolute value).

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-77943 (JP, A) JP-A-2-164282 (JP, A) JP-A-4-36997 (JP, A) JP-A-60-1985 30099 (JP, A) JP-A-4-322118 (JP, A) JP-A-5-135964 (JP, A) JP-A-5-90897 (JP, U) JP-A-1-134398 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H05B 41/24 H02M 7/48

Claims (1)

(57) [Claims] 1. A sign light power supply device for boosting an AC voltage having a frequency higher than a commercial frequency from an inverter by a transformer and applying the boosted voltage to a sign light, wherein the transformer is provided with two transformers. The windings are connected in parallel with each other so that the connection polarity can be switched by a polarity change switch. One end of each secondary winding of the two transformers is connected to each other. An output terminal is connected to each other end of the wire, and the output voltages of the two secondary windings are added and output by switching of the polarity switch and connection of the three output terminals,
A power supply for a sign lamp, wherein a subtraction output and a parallel connection output are possible.