JP2006054079A - Explosion-proof type laminated display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an explosion-proof type laminated display device which can be arranged at a dangerous area without necessitating a large glass tube, and easily installed and transported, capable of preventing cost increase and effectively utilizing a sound device. <P>SOLUTION: The explosion-proof type laminated display device is composed of a laminated display light source 1 with an essentially safe explosion-proof structure, and a base stand 2 with a pressure resistant explosion-proof structure housing a safety retaining circuit 23. A power supply wire (not illustrated) supplying power to display parts 11A to 11C of the laminated display light source 1 is made to penetrate through a lead-in port for pressure resistant explosion proof 22 arranged at the side face of the base stand 2, and a power supply wire (not illustrated) of the laminated display light source 1 is made to penetrate through a lead-in port for pressure resistant explosion proof 21 arranged on the upper face of the base stand 2. The laminated display light source 1 is connected to the power supply wire at the inside of the base stand 2 through a conductive wire and the safety retaining circuit 23. For example, silicon powder or resin is filled in the base stand 2 after the connection of the safety retaining circuit 23 and conductive wire and the power supply wire is completed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an explosion-proof laminated display device that is installed in a hazardous area such as a flammable gas atmosphere and displays an operation state of the device by selectively lighting a laminated display portion.

  2. Description of the Related Art Conventionally, a stacked indicator lamp in which a plurality of indicator lamps are stacked has been used in order to display an operation state of an apparatus such as a machine tool in a factory (for example, see Patent Document 1). For example, a blue indicator lamp, a yellow indicator lamp, and a red indicator lamp are stacked in this order from bottom to top.A blue indicator lamp when the device is normal, a yellow indicator lamp when a minor abnormality occurs, When an abnormality occurs, the red indicator lights are turned on. In addition, some laminated indicator lamps include, for example, an alarm device such as an alarm that rings when a serious abnormality occurs (see, for example, Patent Document 2).

  When an abnormality occurs in the apparatus, it is necessary to immediately perform an operation for avoiding the abnormality. Therefore, it is necessary to make the display state of the laminated indicator light visible at any position in the vicinity. For this reason, the laminated display lamp generally has a cylindrical shape and is configured to emit display light over the entire circumference.

  Since the driving power of the indicator lamp is supplied to the laminated indicator lamp, if the device whose operation status should be displayed by the laminate indicator lamp is installed in a hazardous area such as a flammable gas atmosphere area, the indicator is displayed over the entire circumference. The laminated indicator lamp must have an explosion-proof structure while maintaining the structure that emits light.

  For this reason, as shown in FIG. 4, for example, the conventional laminated display lamp 100 is housed in a flameproof explosion-proof structure container 200 having a cylindrical explosion-proof glass tube 201 and used in a hazardous area. The explosion-proof explosion-proof structural container 200 includes a pressure-proof explosion-proof upper lid 202 and a pressure-proof explosion-proof base 203 that close the upper and lower ends of the pressure-proof explosion-proof glass tube 201. The glass tube 201 covers the periphery of the laminated display lamp 100 placed on the base 203. The base 203 is provided with a pressure-proof explosion-proof inlet 204 and houses an external wiring terminal block 205 therein. The laminated indicator lamp 100 is connected to a power supply line penetrating the service port 204 inside the base 203 through an external wiring terminal block 205.

The laminated display lamp 100 is covered with a translucent glass tube 201 sealed by an upper lid 202 and a base 203, and is explosion proof while maintaining a state in which display light can be seen from the entire circumference. Structured and can be used safely in hazardous areas.
JP 07-326209 A JP 2004-062653 A

  However, the conventional configuration requires a large glass tube that can cover the periphery of the laminated display lamp, and there is a problem that not only the cost increases but also the installation work and the transport work become difficult. In addition, high processing accuracy is required to close the upper and lower ends of the glass tube with the upper lid and base, and when the upper and lower ends of the glass tube and the upper lid and base are fixed using resin, the environmental test is passed. It is necessary to prepare a plurality of types of glass tubes according to the size of the laminated indicator lamp, and these also cause an increase in cost. Furthermore, there is a problem that the sound generated internally for covering the periphery of the multilayer indicator lamp is difficult to be transmitted to the outside, and the acoustic device that may be provided in the multilayer indicator lamp cannot be used effectively.

  The object of the present invention is to enable placement in a hazardous area without the need for a large glass tube covering the periphery, to prevent an increase in cost, and to facilitate installation work and transportation work. Another object of the present invention is to provide an explosion-proof laminated display device that can effectively use an acoustic device.

In order to solve the above-described problem, the present invention provides an intrinsically safe explosion-proof laminated display lamp configured by laminating a plurality of display units, at least one of which is a display that emits display light.
A flameproof explosion-proof base having at least a pressure-proof explosion-proof inlet through which the power line penetrates, and housing a safety holding circuit for connecting the power line to the laminated indicator lamp;
It is characterized by including.

  In this configuration, an intrinsically safe explosion-proof laminated indicator lamp having an indicator with sufficiently low power consumption of the light source is connected to the power supply line via a safety holding circuit housed in the base. Therefore, the explosion-proof structure of the multilayer display lamp is maintained without being housed in the explosion-proof container, and a glass tube that covers the periphery of the multilayer display lamp in a state where the display light can be emitted outside in the hazardous area becomes unnecessary.

  As the laminated display lamp, one in which one of the display units is an acoustic device is used. Since the periphery of the multilayer indicator lamp is not covered, the sound generated by the multilayer indicator lamp is reliably transmitted to the outside, so that the multilayer indicator lamp equipped with the acoustic device can be used.

  The said base is made into a sand filling explosion-proof structure or a resin filling explosion-proof structure. The explosion-proof structure of the base is easily realized by sand filling or resin filling.

  A connector for detachably connecting the laminated indicator lamp and the safety holding circuit in the base is provided. Stacked indicator lamps combined on the same base can be easily replaced.

  The safety holding circuit connects the plurality of display units in series to a single safety holder, and selects an input side and an output side of at least one display unit of the plurality of display units by a short-circuit means. Short circuit. The number of safety holders that should be provided for the plurality of display units is reduced, and the cost is reduced.

  According to the present invention, the explosion-proof structure of the multilayer indicator lamp can be maintained without being housed in the explosion-proof container, and the glass tube that covers the periphery of the multilayer indicator lamp in a state where the indicator light can be emitted outside in the hazardous area. It can be made unnecessary. For this reason, an increase in cost can be prevented, installation work and transportation work can be facilitated, and the acoustic device provided in the laminated indicator lamp can be used effectively.

  The base can be easily made into an explosion-proof structure by sand filling or resin filling, and the cost can be further reduced.

  By connecting the laminated indicator lamp and the safety holding circuit in a detachable manner with the connector, it is possible to easily replace the laminated indicator lamp combined with the same base.

  A plurality of displays by connecting a plurality of display units of the laminated indicator lamp in series to a single safety holder and selectively short-circuiting the input side and the output side of at least one display unit. The safety retainer to be provided for the part can be single, and the cost can be further reduced.

  FIG. 1 is a diagram showing a configuration of an explosion-proof laminated display device according to an embodiment of the present invention. FIG. 1 (A) shows a state in which a laminated indicator lamp and a base are integrated, and FIG. Indicates a state in which the laminated indicator lamp and the base are separated. The explosion-proof laminated display device 10 of the present invention includes a laminated indicator lamp 1 having an intrinsically safe explosion-proof structure and a base 2 having a pressure-proof explosion-proof structure. The laminated display lamp 1 is configured by, for example, three display units 11A to 11C stacked one above the other. Each of the display units 11A to 11C is a display device according to the present invention in which a light source with a small power consumption such as an LED is housed in a cylindrical lens made of a translucent resin. Thereby, the laminated indicator lamp 1 has an intrinsically safe explosion-proof structure. Note that the number of stacked display portions is not limited to three.

  The base 2 has pressure-proof explosion-proof inlets 21 and 22 on the upper surface and side surfaces, and houses a safety holding circuit 23 therein. A power line (not shown) for supplying power to the display units 11A to 11C of the laminated display lamp 1 passes through the explosion-proof explosion-proof inlet 22 provided on the side surface of the base 2. A lead wire (not shown) of the laminated display lamp 1 passes through the explosion-proof inlet 21 provided on the upper surface of the base 2. The laminated indicator lamp 1 is connected to a power supply line through a conducting wire and a safety holding circuit 23 inside the base 2.

  After the connection between the safety holding circuit 23 and the conducting wire and the power supply line is completed, the base 2 can be filled with, for example, silicon powder or resin so as to have a sand filling explosion-proof structure or a resin filling explosion-proof structure. . Thereby, it is not necessary to make the casing 2 of the base 2 itself have a pressure-proof explosion-proof structure, and the base 2 can be manufactured at low cost.

  In the state shown in FIG. 1A, the explosion-proof inlet 21 is constituted by a plug and a socket, one of which is fixed to the bottom surface of the laminated indicator lamp 1 and the other of which is fixed to the top surface of the base 2. The laminated display lamp 1 and the base 2 are connected. Thereby, the laminated indicator lamp 1 is fixed in a state of being placed on the upper surface of the base 2.

  In the state shown in FIG. 1B, the intrinsically safe explosion-proof inlet 24 is provided on the bottom surface of the laminated indicator lamp 1 and the explosion-proof inlet 21 is provided on the upper surface of the base 2. 24 and the explosion-proof explosion-proof inlet 21 are connected by a cable 25, whereby the laminated indicator lamp 1 is separated from the base 2. Thereby, the laminated indicator lamp 1 can be installed at a desired place by the same operation as that of an ordinary laminated indicator lamp having no explosion-proof structure.

  Further, for example, in the base 2, a connector is provided between the laminated indicator lamp 1 and the safety holding circuit 23, and the laminated indicator lamp 1 and the safety holding circuit 23 can be detachably connected via the connector. it can. Thereby, the replacement operation of the laminated indicator lamp can be easily performed when the laminated indicator lamp 1 fails or when the usage is changed. In this case, the same base 2 can be used even when the size of the laminated display lamp to be used changes, and it is necessary to prepare a plurality of sizes of bases 2 according to the size of the laminated display lamp. Absent.

  The explosion-proof laminated display device 10 is composed of a laminated indicator lamp 1 having an intrinsically safe explosion-proof structure and a base 2 having a pressure-proof explosion-proof structure, and does not require an expensive, heavy and easily damaged glass tube. Therefore, installation work and transportation work can be easily performed, and cost reduction can be realized.

  FIG. 2 is a diagram showing a configuration of a safety holding circuit in the multilayer display device. As shown in FIG. 2A, the safety holding circuit 23 includes safety holders 23 </ b> A to 23 </ b> C connected to the light source LEDs 12 </ b> A to 12 </ b> C provided in the display units 11 </ b> A to 11 </ b> C of the laminated indicator lamp 1. Each of the LEDs 12A to 12C is configured with a separate safety holding circuit. Each of the safety retainers 23A to 23C is configured by current limiting means such as a Zener diode or a resistor.

  The safety holding circuit 23 can also be configured as shown in FIG. In the example shown in FIG. 2B, a single safety holding circuit in which LEDs 12A to 12C for light sources provided in the display units 11A to 11C of the laminated indicator lamp 1 are connected in series from a single safety holder 23D. The short circuit means 13A-13C which short-circuits between each input terminal and output terminal of LED12A-12C in this safety holding circuit is provided. Each of the short-circuit means 13A to 13C is configured by, for example, a photocoupler.

  In this configuration, for example, when the short-circuit means 13B and 13C corresponding to the LEDs 12B and 12C are short-circuited by a signal supplied via the signal lines 14B and 14C, the power is supplied from the safety holder 23D to the LEDs 12A, short-circuit means 13B, and short-circuit means 13C. In order and return to the safety holder 23D without passing through the LEDs 12B and 12C. For this reason, only the LED 12A is lit, and the LEDs 12B and 12C are not lit. Thus, by selectively enabling the short-circuit means 13A to 13C, the LED 12A to 12C corresponding to the activated short-circuit means can be turned off.

  As described above, according to the configuration shown in FIG. 2B, the number of relatively expensive safety retainers can be reduced as compared with the configuration shown in FIG. .

  FIG. 3 is a diagram showing a configuration of a safety holding circuit in an explosion-proof laminated display device according to another embodiment of the present invention. As an example, the explosion-proof laminated display device according to this embodiment is obtained by laminating four layers of display units that house the LEDs 12A to 12C and the alarm device 32, respectively. The alarm device 32 is the acoustic device of the present invention and rings when an abnormality occurs. Since this explosion-proof laminated display device does not include a pressure-proof explosion-proof glass tube covering the periphery of the laminated display lamp, an alarm can be transmitted to the surroundings when the alarm device 32 rings.

  As shown in FIG. 3A, the safety holding circuit 23 accommodated in the base 2 includes safety holders 23A to 23C corresponding to the respective LEDs 12A to 12C and a safety holder 23E corresponding to the alarm device 32. I have. The safety holders 23A to 23C include current limiting means corresponding to the current value flowing through the LEDs 12A to 12C. If the LEDs 12A to 12C have the same specifications, the safety holders 23A to 23C can have the same configuration. The safety holder 23E includes a current limiting unit corresponding to the current value flowing through the alarm device 32. Generally, since the current value flowing through the alarm device 32 is different from the current value flowing through the LEDs 12A to 12C, the safety holder 23E has a different configuration from the safety holders 23A to 23C.

  In this way, the safety holding circuit 23 shown in FIG. 3A constitutes a separate safety holding circuit for each of the LEDs 12A to 12C and the alarm device 32.

  The safety holding circuit 23 shown in FIG. 3 (B) includes a single safety holder 33 constituted by current limiting means corresponding to each of the LEDs constituting the LEDs 12A to 12C and the alarm device 32. LEDs 12A to 12C are connected in series to the current limiting means corresponding to the LEDs of the safety holder 33, and short-circuit means 13A to 13C for selectively short-circuiting between the input terminals and the output terminals of the LEDs 12A to 12C are provided. I have. An alarm device 32 and a short circuit device 34 are connected in series to the current limiting device corresponding to the alarm device 32 of the safety holder 33. Each of the short-circuit means 13A to 13C and 34 is constituted by, for example, a photocoupler.

  In this configuration, for example, when the short-circuit means 13B and 13C corresponding to the LEDs 12B and 12C are short-circuited by a signal supplied via the signal lines 14B and 14C, the power is supplied from the safety holder 33 to the LEDs 12A, short-circuit means 13B, and short-circuit means 13C. In order, and returns to the safety holder 33 without passing through the LEDs 12B and 12C. For this reason, only the LED 12A is lit, and the LEDs 12B and 12C are not lit. Thus, by selectively enabling the short-circuit means 13A to 13C, the LED 12A to 12C corresponding to the activated short-circuit means can be turned off.

  When the short-circuit means 34 is short-circuited by a signal supplied via the signal line 14 </ b> D, the power source returns from the safety holder 33 to the safety holder 33 via the alarm device 32 and the short-circuit means 34. Therefore, when the short-circuit means 34 is activated, the alarm device 32 sounds.

  Thus, according to the configuration shown in FIG. 3B, the number of relatively expensive safety retainers can be reduced as compared to the configuration shown in FIG. .

It is a figure which shows the structure of the explosion-proof laminated display apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the safety holding circuit in the said explosion-proof laminated display apparatus. It is a figure which shows the structure of the safety holding circuit in the explosion-proof laminated display apparatus which concerns on another embodiment of this invention. It is a figure which shows the structure of the conventional explosion-proof laminated display apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laminated display lamp 2 Base 10 Explosion-proof laminated display apparatus 11A-11C Display part 12A-12C LED
13A to 13C Short-circuit means 21 and 22 Explosion-proof inlet 23 Safety holding circuit 23A to 23D Safety holder

Claims (5)

An intrinsically safe explosion-proof laminated display lamp comprising a plurality of display parts, each of which is a display that emits display light; and
A flameproof explosion-proof base having at least a pressure-proof explosion-proof inlet through which the power line penetrates, and housing a safety holding circuit for connecting the power line to the laminated indicator lamp;
An explosion-proof multilayer display device comprising:   2. The explosion-proof laminated display device according to claim 1, wherein one of the display units of the laminated display lamp is an acoustic device.   The explosion-proof laminated display device according to claim 1, wherein the base has a sand-filled explosion-proof structure or a resin-filled explosion-proof structure.   The explosion-proof laminated display device according to claim 1, wherein the laminated display lamp and the safety holding circuit housed in the base are detachably connected via a connector.   The safety holding circuit connects the plurality of display units in series to a single safety holder and selectively short-circuits an input side and an output side of at least one display unit of the plurality of display units. The explosion-proof multilayer display device according to claim 1, further comprising a short-circuit unit that performs the operation.

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