EP3128526A1

EP3128526A1 - Indicator-equipped switch

Info

Publication number: EP3128526A1
Application number: EP15772311.5A
Authority: EP
Inventors: Kazuya Baba; Katsuya Imai; Toshiyuki Takii; Atsushi Nakamura; Kiwamu Shibata
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2014-03-31
Filing date: 2015-02-03
Publication date: 2017-02-08
Also published as: TWI595525B; EP3128526A4; TW201603091A; CN106133867A; PH12016501936B1; JP2015195118A; PH12016501936A1; CN106133867B; JP6327553B2; WO2015151378A1

Abstract

An objective of the present invention is to provide an indicator-equipped switch which reduces the possibility that the light-emitting element is not turned at a stop of power supply to the load while reducing cases where the light-emitting element is erroneously turned on when a closed circuit is formed due to stray capacitance. An indicator-equipped switch (5) alternately switches between a first state and a second state in response to a switching operation of alternately switching a common terminal (51) between a first switching terminal (52) and a second switching terminal (53). In the first state, an applied voltage to a load (e.g., a lighting load (6)) is higher than or equal to an operating voltage and a first light-emitting element (e.g., first light-emitting diode (54)) is turned off. In the second state, the applied voltage to the load is lower than the operating voltage and the first light-emitting element is turned on.

Description

Technical Field

The present invention relates to indicator-equipped switches, and specifically to an indicator-equipped switch including a light-emitting element as an indicator.

Background Art

A switching device having a back surface side to be embedded in a wall on installation has been provided (for example, JP 2008-171730 A (hereinafter referred to as "Document 1")). The switching device described in Document 1 includes a so-called three-way switch including a common terminal, a first switching terminal, and a second switching terminal. The switching device also includes a series circuit of a resistor and a neon lamp which are connected between the first switching terminal and the second switching terminal of the three-way switch.
A system is constructed in which, for example, two switching devices each including such a three-way switch are used to turn ON/OFF a lighting load. In the system, the first switching terminals of the switching devices are connected to each other via an electric cable, and the second switching terminals of the switching devices are connected to each other via an electric cable. A series circuit of a commercial power source and the lighting load is connected between the common terminals of the switching devices via an electric cable.
In the above-described system, when the lighting load is in an off state, the common terminal of one of the switching devices is connected to the first switching terminal and the common terminal of the remaining one of the switching devices is connected to the second switching terminal. The neon lamps of both of the switching devices are in an on state due to electric power supplied from the commercial power source.
From this state, the common terminal of the one switching device is switched to the second switching terminal. Then, electric power is supplied from the commercial power source to the lighting load, thereby turning on the lighting load. At this time, currents flowing to the neon lamps are stopped, so that both of the neon lamps are turned off.
As described above, both of the neon lamps are in the on state when the lighting load is in the off state. Therefore, a user can locate the position of the switching devices based on emission of light from the neon lamps.
While the switching device disclosed in Document 1 includes the neon lamp as an indicator to indicate the position of the switching device, switching devices including light-emitting diodes (LEDs), instead of the neon lamps, have also been provided.
The threshold voltage of the light-emitting diode is lower than that of the neon lamp. Therefore, when, stray capacitance is caused, for example, between each of the electric cables and ground or between the electric cables, and a closed circuit is formed by the stray capacitance, the possibility of erroneous light emission of the light-emitting diode is higher than that of the neon lamp.
The neon lamp has voltage characteristics as illustrated in FIG. 7A. According to FIG. 7A, the neon lamp is turned on when a voltage V1 across the neon lamp reaches a lighting start voltage V11, and then, the voltage V1 decreases to a lighting maintaining voltage V12 (V12 <V11) (see the solid line a1 in FIG. 7A).
FIG. 8 is a schematic circuit diagram illustrating a system including two switching devices. In this system, a series circuit of a neon lamp 71 A and a resistor 72 is connected in parallel to a series circuit of a neon lamp 71B and a resistor 72, and a series circuit of a lighting load 6 and a commercial power source 7 is connected between both ends of the series circuits connected in parallel. In FIG. 8, the illustration of a three-way switch is omitted.
Neon lamps individually have different voltage characteristics. For example, it is assumed that a neon lamp having a lighting start voltage V11 is included in one of the switching devices and a neon lamp having a lighting start voltage V 13 (V 13 > V11) is included in the remaining one of the switching devices. In this case, the neon lamp having the lighting start voltage V11 is turned on when the voltage V1 reaches the lighting start voltage V11, and then, the voltage V1 decreases to a lighting maintaining voltage V12.
After the voltage V1 has decreased to the lighting maintaining voltage V12, the voltage V1 starts to increase again, and when the voltage V1 reaches the lighting start voltage V13 of the neon lamp 71B, the neon lamp 71B is also turned on. Then, the voltage V1 decreases to a lighting maintaining voltage V14. Thereafter, the voltage V1 gradually increases (the solid line a2 in FIG. 7B).
When the impedance of the lighting load 6 is high, the voltage V1 at the time of turning off the lighting load 6 decreases, and therefore, the neon lamp 71B may not be turned on.

Summary of Invention

In view of the foregoing, it is an object of the present invention to provide an indicator-equipped switch which reduces the possibility that a light-emitting element is not turned on at a stop of power supply to a load while reducing cases where a light-emitting element is erroneously turned on when a closed circuit is formed due to stray capacitance.
An indicator-equipped switch of the present invention includes a common terminal, a first switching terminals, a second switching terminal, a light-emitting element, a resistor, and a voltage regulator diode. The light-emitting element is connected between the first switching terminal and the second switching terminal. The resistor is connected in series to the light-emitting element and is configured to limit a current flowing to the light-emitting element. The voltage regulator diode is connected in series to the light-emitting clement and the resistor. The indicator-equipped switch alternately switches between a state where an applied voltage to the load is higher than or equal to an operating voltage and the light-emitting element is turned off and a state where the applied voltage to the load is lower than the operating voltage and the light-emitting element is turned on in response to a switching operation of alternately switching the common terminal between the first switching terminal and the second switching terminal. Here, the operating voltage refers to a voltage value which the connected load requires to operate.

Brief Description of Drawings

FIG. 1 is a schematic circuit diagram illustrating a lighting system including an indicator-equipped switch of the present embodiment;
FIG. 2 is an exploded perspective view illustrating the switching device including the indicator-equipped switch of the present embodiment;
FIGS. 3A and 3B are graphs illustrating the operation of the indicator-equipped switch of the present embodiment;
FIG. 4 is a schematic circuit diagram illustrating a lighting system including another indicator-equipped switch of the present embodiment;
FIG. 5 is a schematic circuit diagram of a lighting system including yet another indicator-equipped switch of the present embodiment;
FIG. 6 is a schematic circuit diagram illustrating a lighting system including still another indicator-equipped switch of the present embodiment;
FIGS. 7A and 7B are graphs illustrating the operation of a known switching device; and
FIG. 8 is a schematic circuit diagram illustrating a system including the known switching device.

Description of Embodiment

An indicator-equipped switch according to an embodiment of the present invention will be specifically described below with reference the drawings. In the following description, unless otherwise stated, the upward and downward direction, the forward and rearward direction, and the right and left direction are defined as shown in FIG. 2. That is, the longitudinal direction of a plate 4 is the upward and downward direction, the width direction of the plate 4 is the right and left direction, and a direction orthogonal to the longitudinal direction and the width direction of the plate 4 is the forward and rearward direction.
FIG. 2 is an exploded perspective view illustrating a switching device including the indicator-equipped switch. The switching device includes a mounting frame 1 for an apparatus (hereinafter referred to as a mounting frame), a piano handle switch 10, and the plate 4.
As illustrated in FIG. 2, the switch 10 includes a switch body 100 and an operation handle 110.
The switch body 100 has a rectangular box shape elongated in the right and left direction. The switch body 100 has a front surface to which a push button 101 movable in the forward and rearward direction is attached. A switching mechanism is configured such that whenever the push button 101 is pushed, the state of an indicator-equipped switch 5 (see FIG. 1) accommodated in the switch body 100 is switched. The indicator-equipped switch 5 will be described later.
The front surface of the switch body 100 has a left side area to which a light transmissive lamp cover 102 is attached at the center in the upward and downward direction. The switch body 100 accommodates a first light-emitting diode 54 (see FIG. 1) included in the indicator-equipped switch 5. Light emitted from the first light-emitting diode 54 penetrates through the lamp cover 102 and is irradiated to the front. Here, in the present embodiment, the first light-emitting diode 54 forms a light-emitting element (first light-emitting element).
The switch body 100 has a left side surface and a right side surface each having two attachment pawls 103 to attach the switch body 100 to the mounting frame 1. The right side surface of the switch body 100 has a slit formed around a portion where the two attachment pawls 103 are provided. The portion where the two attachment pawls 103 are provided (the portion is referred to as a movable piece 104) has a front end supported by the switch body 100 in a cantilever manner.
Therefore, a projection 105 provided at a rear portion of the movable piece 104 is inwardly pressed, thereby moving the two attachment pawls 103 provided to the movable piece 104 into the switch body 100.
The left side area of the front surface of the switch body 100 has two columnar shafts 106 provided on opposing sides of the lamp cover 102 in the upward and downward direction to support the operation handle 110.
The switch body 100 has a rear portion having left and right areas each having two electric cable insertion holes to which electric cables are to be inserted. The switch body 100 accommodates connection terminals each having a quick connection structure and electrically connected to a common terminal 51, a first switching terminal 52, and a second switching terminal 53 which will be described later. Core cables of the electric cables inserted through the electric cable insertion holes are to be connected to the connection terminals.
As illustrated in FIG. 2, the operation handle 110 has a rectangular plate shape having a dimension sufficiently larger than a front surface of the push button 101. The operation handle 110 has a front surface in a right side area of which an oval hole is formed at the center in the upward and downward direction to pass through the operation handle 110 in the forward and rearward direction. The hole has a light transmitting plate 111 embedded therein.
The operation handle 110 has a back surface provided with a prism configured to guide light output through the lamp cover 102 of the switch body 100 to the light transmitting plate 111. In this way, the light transmitting plate 111 is illuminated with light of the first light-emitting diode 54 accommodated in the switch body 100, and therefore, this illumination can indicate the position of the switch 10.
The back surface (rear surface) of the operation handle 110 further has bearing sections which are provided at portions facing the shafts 106 of the switch body 100 and to which the shafts 106 are to be pivotally attached. The bearing sections hold the shafts 106 to pivotally support the operation handle 110 on the front surface of the switch body 100 at one side portion (left side portion) in the right and left direction of the operation handle 110.
Therefore, when a right side portion of the operation handle 110 is pressed rearward, the operation handle 110 pivots around the portion supported by the shafts 106, thereby pushing the push button 101 by a projection provided to the rear surface of the operation handle 110.
The mounting frame 1 is made of a synthetic resin or a metal plate to have a rectangular frame shape having a window hole 18 in which the switch body 100 is to be embedded. The mounting frame 1 includes a pair of horizontal beams 11 and a pair of vertical beams 12. The horizontal beams 11 face each other on opposite sides of the window hole 18 in the longitudinal direction (the upward and downward direction in FIG. 2). The vertical beams 12 face each other on opposite sides of the window hole 18 in a direction (right and left direction) crossing the direction in which the horizontal beams 11 face each other. That is, a space surrounded by the pair of horizontal beams 11 and the pair of vertical beams 12 is the window hole 18.
Each of the pair of horizontal beams 11 has an insertion hole 13 into which a screw for fixing the horizontal beam 11 on a building material (for example, wall material) is to be inserted with a back surface side of the horizontal beam 11 abutting on a front surface of the building material. Each of the pair of horizontal beams 11 has a screw hole 14 located more outwardly than the insertion hole 13 (on an upper side or a lower side of the insertion hole 13 in FIG. 2) and formed at the center in the right and left direction.
Each of the pair of vertical beams 12 has a plurality of (for example, eight) through holes 15 into which the attachment pawls 103 of the switch body 100 are to be individually inserted. That is, the two attachment pawls 103 provided to each side of the switch body 100 are individually inserted into corresponding through holes 15, thereby attaching the switch body 100 to the mounting frame 1 with a front end of the switch body 100 projecting frontward from the window hole 18.
The mounting frame 1 is fixed to the building material by being attached to a switch box embedded in the building material with a rear surface (back surface) of the horizontal beam 11 abutting on a peripheral portion of a hole in which a component is to be embedded and which is formed in the building material. That is, two bolts inserted into the insertion holes 13 of the upper and lower horizontal beams 11 are screwed into screw holes of the switch box. Note that when the switch box is not embedded, the mounting frame 1 is fixed to the building material by using a known metal clip.
As illustrated in FIG. 2, the plate 4 includes a plate body 2 which is attachable to the mounting frame 1 and a plate cover 3 which can be detachably attached to the plate body 2 to cover the plate body 2.
As illustrated in FIG. 2, the plate body 2 is made of a synthetic resin material to have a rectangular frame shape having a pair of horizontal pieces 21 and a pair of vertical pieces 22. Here, a window hole 20 surrounded by the pair of horizontal pieces 21 and the pair of vertical pieces 22 is provided at a position which overlaps the window hole 18 of the mounting frame 1 in the forward and rearward direction when the plate body 2 is attached to the mounting frame 1.
Each of the pair of horizontal pieces 21 has an insertion hole 23 which is formed at the center in the right and left direction and into which a screw is to be inserted. Each of the pair of vertical pieces 22 has rectangular through holes 24 formed at the center and at both side portions in the longitudinal direction (upward and downward direction). One of the horizontal pieces 21 (the horizontal piece 21 on the lower side in FIG. 2) has recesses 25 which are open frontward and downward and which are provided on right and left side portions of the lower end of the one horizontal piece 21.
As illustrated in FIG. 2, the plate cover 3 includes a front wall 30 and a side wall 31 which are integrally formed as a synthetic resin molding. The front wall 30 has a rectangular shape with four rounded corners when viewed in the forward and rearward direction. The front wall 30 has a curved surface rising frontward from the edge to the center of the front wall 30. The front wall 30 has a window hole 32 passing through the center of the front wall 30. The front wall 30 has a rear surface provided with hooks which are formed at portions corresponding to the plurality of through holes 24 in the plate body 2 and are to be inserted into the through holes 24 so as to be hooked on the peripheral portion.
The side wall 31 has an annular shape with a front edge of the side wall 31 being connected to the rim of the front wall 30. The side wall 31 is inclined outwardly toward the front. The side wall 31 has projections at positions facing the recesses 25 of the plate body 2.
Next, the indicator-equipped switch 5 according to the present embodiment will be described.
FIG. 1 is a schematic circuit diagram illustrating a lighting system including the indicator-equipped switch 5. The lighting system includes two indicator-equipped switches 5 and a lighting load 6 (load).
The indicator-equipped switch 5 includes the common terminal 51, the first switching terminal 52, the second switching terminal 53, the first light-emitting diode 54, a first resistor 55, a voltage regulator diode 56, and a protection diode 57. In the present embodiment, a bidirectional voltage regulator diode is used as the voltage regulator diode 56. However, the voltage regulator diode is not necessarily bidirectional as long as the voltage regulator diode is capable of operating at least unidirectionally (in the forward direction of the first light-emitting diode 54).
A series circuit of the lighting load 6 and a commercial power source 7 is connected between the common terminals 51 of the indicator-equipped switches 5 via electric cables 63. The first switching terminals 52 are connected to each other via an electric cable 61, and the second switching terminals 53 are connected to each other via an electric cable 62. In each of the indicator-equipped switch 5, the common terminal 51 is alternately switched between the first switching terminal 52 and the second switching terminal 53 whenever the push button 101 of the switch 10 is pushed.
In each of the indicator-equipped switches 5, a series circuit of the first resistor 55, the first light-emitting diode 54, and the voltage regulator diode 56 is connected between the first switching terminal 52 and the second switching terminal 53. Moreover, the protection diode 57 is connected in inversely parallel to the first light-emitting diode 54 between both ends of the first light-emitting diode 54.
Here, in the present embodiment, the first light-emitting diode 54 is connected in an orientation in which the anode of the first light-emitting diode 54 faces the first switching terminal 52 and the cathode of the first light-emitting diode 54 faces the second switching terminal 53, and the protection diode 57 is connected in an orientation in which the anode of the protection diode 57 faces the second switching terminal 53 and the cathode of the protection diode 57 faces the first switching terminal 52.
In this lighting system, in a state where the common terminals 51 of the indicator-equipped switches 5 are connected to the first switching terminals 52 or in a state where the common terminals 51 of the indicator-equipped switches 5 are connected to the second switching terminals 53, an alternative-current power output from the commercial power source 7 is supplied to the lighting load 6, thereby turning on the lighting load 6. At this time, the potential difference between the first switching terminals 52 and the potential difference between the second switching terminals 53 are substantially zero. Therefore, a current does not flow through the first light-emitting diodes 54, and none of the first light-emitting diodes 54 is turned on. That is, when the lighting load 6 is in the on state, the first light-emitting diode 54 is not turned on.
Here, in the present embodiment, the applied voltage to the lighting load 6 at the time of turning on the lighting load 6 is an operating voltage.
From this state (for example, state illustrated in FIG. 1), the common terminal 51 of one of the indicator-equipped switches 5 (for example, the indicator-equipped switch 5 on the left in FIG. 1) is switched to the second switching terminal 53. Then, the lighting load 6 is turned off, and alternative-current power is supplied to the first light-emitting diodes 54 of the indicator-equipped switches 5.
At this time, each first light-emitting diode 54 is turned on by a current which flows every half time period during which a voltage applied to the first light-emitting diode 54 is in the forward direction. Moreover, at this time, the alternative-current power is also supplied to the lighting load 6. However, the current value of the alternative-current power is limited by the first resistor 55, and therefore, the lighting load 6 is not turned on. That is, at this time, the applied voltage to the lighting load 6 is lower than the operating voltage.
Here, when the first light-emitting diode 54 is used as an indicator as in the case of the indicator-equipped switch 5 of the present embodiment, the first light-emitting diode 54 may be erroneously turned on due to stray capacitance caused between each electric cable and ground or between the electric cables because the threshold voltage of the first light-emitting diode 54 is lower than that of the neon lamp.
To solve the problem, in the present embodiment, the voltage regulator diode 56 is connected in series to the first light-emitting diode 54. In this case, even when the stray capacitance is caused between each electric cable and ground or between the electric cables, the applied voltage to the first light-emitting diode 54 is clamped by the voltage regulator diode 56. Therefore, no current flows to the first light-emitting diode 54, and the first light-emitting diode 54 is not turned on. That is, it is possible to reduce cases where the first light-emitting diode 54 is erroneously turned on.
Moreover, the first light-emitting diode 54 has such electrical characteristics that an energizing current monotonously increases with respect to the applied voltage as compared to the neon lamp. This further provides the advantage that even when the impedance of the connected lighting load 6 is high, the possibility that the first light-emitting diode 54 is not turned on is lower than the possibility that the neon lamp is not turned on.
Note that the above-described stray capacitance is often caused between the electric cables at the same time as the generation of the stray capacitance between the electric cable and ground. Therefore, in order to reduce cases where the first light-emitting diode 54 is erroneously turned on, the breakdown voltage of the voltage regulator diode 56 is preferably set to be equal to or higher than a half of the maximum value of the power supply voltage of the commercial power source 7.
It is assumed that a first light-emitting diode 54 having a lighting start voltage V21 is connected to one of the indicator-equipped switches 5 and a first light-emitting diode 54 having a lighting start voltage V22 (V22 > V21) is connected to the remaining one of the indicator-equipped switches 5. In the following description, the first light-emitting diode 54 having the lighting start voltage V21 is referred to as a first light-emitting diode 54A, and the first light-emitting diode 54 having the lighting start voltage V22 is referred to as a first light-emitting diode 54B.
When neon lamps 71A and 71B are used as indicators as in the case of a known switching device, if the impedance of the lighting load 6 is high, the applied voltage to the neon lamps 71 A and 71 B decreases even with the lighting load 6 being in an off state. As a result, it is highly possible that the neon lamp 71B having a relatively high lighting start voltage is not turned on.
In contrast, in the present embodiment, the first light-emitting diodes 54A and 54B are used as indicators. The first light-emitting diodes 54A and 54B have such electrical characteristics that the energizing current monotonously increases with respect to the applied voltage. Therefore, even when the first light-emitting diode 54A having a low threshold voltage starts to light up, a voltage applied to the first light-emitting diode 54B having a high threshold voltage does not decrease, and even when the impedance of the lighting load 6 is high, the possibility that the first light-emitting diodes 54A and 54B are not turned on is lower than the possibility that the neon lamps 71 A and 71B are not turned on.
Therefore, the first light-emitting diode 54A is turned on when an applied voltage V2 to the first light-emitting diodes 54A and 54B reaches the lighting start voltage V21 (see solid line a3 in FIG. 3A). Thereafter, the applied voltage V2 to the first light-emitting diodes 54A and 54B further increases, and the first light-emitting diode 54B is turned on when the applied voltage V2 reaches the lighting start voltage V22 (see solid line a4 in FIG. 3B). Note that when a bidirectional voltage regulator diode is used as the voltage regulator diode 56 as in the present embodiment, a protection diode 57 having a low breakdown voltage can be used. Note that the solid line b1 in FIG. 3A represents a current flowing through the first light-emitting diode 54A, and the solid line b2 in FIG. 3B represents a current flowing through the first light-emitting diode 54B.
FIG. 4 is a schematic circuit diagram illustrating a lighting system including another indicator-equipped switch 5 of the present embodiment. In this indicator-equipped switch 5, a protection diode 57 is connected in inversely parallel to a first light-emitting diode 54, and a second resistor 58 is connected in series to the protection diode 57. Other configurations are similar to those of the indicator-equipped switch 5 illustrated with reference to FIG. 1, and thus, description thereof is omitted here.
As described above, the second resistor 58 is connected in series to the protection diode 57, and therefore, a reverse current which does not contribute to turn on of the first light-emitting diode 54 can be limited, and a leakage current can be reduced.
FIG. 5 is a schematic circuit diagram illustrating a lighting system including yet another indicator-equipped switch 5 of the present embodiment. The indicator-equipped switch 5 includes a second light-emitting diode 59 (second light-emitting element) as a protection diode. Other configurations are similar to those of the indicator-equipped switch 5 illustrated with reference to FIG. 1, and thus, description thereof is omitted here.
The second light-emitting diode 59 is used as the protection diode to reduce a reverse voltage applied to a first light-emitting diode 54, thereby increasing the illuminance of an indicator while protecting the first light-emitting diode 54.
FIG. 6 is a schematic circuit diagram illustrating a lighting system including still another indicator-equipped switch 5 of the present embodiment. The indicator-equipped switch 5 includes a first resistor 55 including a plurality of divided resistors 55A and 55B. Other configurations are similar to those of the indicator-equipped switch 5 illustrated with reference to FIG. 1. and thus, description thereof is omitted here.
One divided resistor 55A is connected between a first switching terminal 52 and the anode of a first light-emitting diode 54. The other divided resistor 55B is connected between a second switching terminal 53 and a voltage regulator diode 56. In this way, the first resistor 55 is divided into the plurality of divided resistors 55A and 55B, thereby reducing a voltage applied to the divided resistors 55A and 55B, which can increase the withstand voltage of the indicator-equipped switch 5 as a whole.
In the present embodiment, the lighting system includes the two indicator-equipped switches 5 and the lighting load 6. However, the lighting system may include, for example, one indicator-equipped switch 5 and the lighting load 6. In the present embodiment, the first resistor 55 is divided into the two divided resistors 55A and 55B. However, the first resistor 55 may be divided into three or more divided resistors and is not limited to the present embodiment.
In the present embodiment, the lighting load 6 has been described as an example of a load controlled by the indicator-equipped switch 5. However, the load is not limited to the lighting load 6 but may be any element which can be turned on/off by the indicator-equipped switch 5. In the present embodiment, the case where the light-emitting element (first light-emitting element) and the second light-emitting element are light-emitting diodes (LEDs) has been described as an example. However, the first light-emitting element and the second light-emitting element are not limited to this example but may be EL elements.
As it is clear from the above-described embodiments, an indicator-equipped switch 5 of a first aspect according to the present invention includes a common terminal 51, a first switching terminal 52, a second switching terminal 53, a first light-emitting diode 54 (light-emitting element), a first resistor 55 (resistor), and a voltage regulator diode 56. The first light-emitting diode 54 is connected between the first switching terminal 52 and the second switching terminal 53. The first resistor 55 is connected in series to the first light-emitting diode 54 and is configured to limit a current flowing to the first light-emitting diode 54. The voltage regulator diode 56 is connected in series to the first light-emitting diode 54 and the first resistor 55. The indicator-equipped switch 5 alternately switches between a first state and a second state in response to a switching operation of alternately switching the common terminal 51 between the first switching terminal 52 and the second switching terminal 53. In the first state, an applied voltage to the lighting load 6 (load) is higher than or equal to an operating voltage and the first light-emitting diode 54 is turned off. In the second state, the applied voltage to the lighting load 6 is lower than the operating voltage and the first light-emitting diode 54 is turned on.
An indicator-equipped switch 5 according to a second aspect of the present invention referring to the first aspect further includes a protection diode 57 connected inversely parallel to the first light-emitting diode 54.
An indicator-equipped switch 5 according to a third aspect of the present invention referring to the first aspect further includes a protection diode 57 connected inversely parallel to the first light-emitting diode 54. The indicator-equipped switch 5 of the third aspect further includes a second resistor 58 in addition to the first resistor 55 as the resistor. The second resistor 58 is connected in series to the protection diode 57 and is connected in parallel to the first light-emitting diode 54 together with the protection diode 57.
In an indicator-equipped switch 5 according to a fourth aspect of the present invention referring to the second or third aspect, the voltage regulator diode 56 is a bidirectional voltage regulator diode.
In an indicator-equipped switch 5 according to a fifth aspect of the present invention referring to any one of the second to fourth aspects, the protection diode is a second light-emitting diode 59 (second light-emitting element) different from a first light-emitting element (the first light-emitting diode 54) as the light-emitting element.
In an indicator-equipped switch 5 according to a sixth aspect of the present invention referring to any one of the first to fifth aspects, the voltage regulator diode 56 has a breakdown voltage whose voltage value is higher than or equal to a half of a maximum value of a power supply voltage of the commercial power source 7.
In an indicator-equipped switch 5 according to a seventh aspect of the present invention referring to any one of the first to sixth aspects, the first resistor 55 includes a plurality of divided resistors 55A and 55B. The plurality of divided resistors 55A are 55B are connected to each other in series between the first switching terminal 52 and the second switching terminal 53.

Claims

An indicator-equipped switch, comprising:
a common terminal;

a first switching terminal;

a second switching terminal;

a light-emitting element connected between the first switching terminal and the second switching terminal;

a resistor connected in series to the light-emitting element and configured to limit a current flowing to the light-emitting element; and

a voltage regulator diode connected in series to the light-emitting element and the resistor, wherein
the indicator-equipped switch alternately switches between a state where an applied voltage to a load is higher than or equal to an operating voltage and the light-emitting element is turned off and a state where the applied voltage to the load is lower than the operating voltage and the light-emitting element is turned on in response to a switching operation of alternately switching the common terminal between the first switching terminal and the second switching terminal.
The indicator-equipped switch according to claim 1, further comprising a protection diode connected inversely parallel to the light-emitting element.
The indicator-equipped switch according to claim 1, further comprising:
a protection diode connected inversely parallel to the light-emitting element; and

a second resistor in addition to a first resistor as the resistor, the second resistor being connected in series to the protection diode and being connected in parallel to the light-emitting element together with the protection diode.
The indicator-equipped switch according to claim 2 or 3, wherein
the voltage regulator diode is a bidirectional voltage regulator diode.
The indicator-equipped switch according to any one of claims 2 to 4, wherein
the protection diode is a second light-emitting element different from a first light-emitting element as the light-emitting element.
The indicator-equipped switch according to any one of claims 1 to 5, wherein
the voltage regulator diode has a breakdown voltage whose voltage value is higher than or equal to a half of a maximum value of a power supply voltage.
The indicator-equipped switch according to any one of claims 1 to 6, wherein
the resistor includes a plurality of divided resistors, and
the plurality of divided resistors are connected in series to each other between the first switching terminal and the second switching terminal.