JPS60127853A - Explosion proof type telephone set - Google Patents

Abstract

PURPOSE:To prevent sympathetic detonation by allowing the output of call detecting means of an interface to light a call lamp at a non-explosion proof area to lead the light of the lamp into the vicinity of a telephone set at the explosion proof area through an optical fiber cable. CONSTITUTION:The interface 40 connected to an exchange 10 is connected to a telephone set 20 through the optical fiber cable 80, the interface 40 is arranged at the non-explosion proof area and the telephone set 20 is arranged at the explosion proof area. The interface 40 is incorporated with relays to detect an external call signal and relays to connect lines as an intermission part of a DC signal between the telephone set and an exchange and relays to transmit externally a dial pulse. Thus, the telephone set is not provided with a calling bell, the calling lamp 101 at the non-explosion area is lighted and its light is led to a display device 102 placed near the telephone set through a handle light guide 103.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in explosion-proof telephone equipment, and particularly to explosion-proof telephones installed in places where there is a risk of explosion, such as ships such as tankers or inside coal mines. This relates to improvements in equipment.

Background of the Invention For example, the pump room of a tanker or the like is likely to be filled with gas that has the risk of causing an explosion, and if a telephone for communication with the outside world is to be installed in such a location, it must be constructed to be explosion-proof. be. This is because the sparks generated by the interruption of the direct current connected directly to the exchange when the handset of the telephone is turned on and off and when dialing, and the gas that is filled with sparks generated at the contacts of the bell when the ringing bell inside the telephone rings. This is because there is a risk of ignition.

Therefore, explosions can be prevented by making the telephone itself or the calling bell explosion-proof.

However, if the ringing bell inside the telephone is sealed to make it explosion-proof, the ringing tone will not be audible or the ringing tone will be very soft. In this case, explosion-proof areas such as pump rooms are very noisy, and this noise may cancel out the ringing tone of the telephone, making it impossible to hear the ringing tone.

In addition, according to the Industrial Safety Research Institute's Factory Equipment Explosion-Proof Guidelines, the power consumption of electric circuits in hazardous areas is
5VAJX or less, and this condition must be met in order to have an explosion-proof structure.

Summary of the Invention In view of the above-mentioned problems, the present inventors first disclosed
proposed an explosion-proof telephone device shown in No. 394. This invention relates to an improvement of the above-mentioned explosion-proof telephone device, and its main purpose is to arrange the telephone except for the ringing bell in an explosion-proof area, and to connect this telephone to an AC 3iA device. The interface that detects the ringing signal and sends the handset on/off signal and dialing signal to the exchange is located in a non-explosion-proof area, and the signals are sent and received between the interface and the telephone using optical fiber cables, and the ringing is not announced. To provide an explosion-proof telephone device capable of preventing an explosion by lighting a call lamp arranged in an explosion-proof area, guiding the light of this lamp to an explosion-proof area in which a telephone is arranged by a bundle light guide, and displaying a call. It is.

To summarize this invention, an interface connected to an exchange is connected to a telephone set by an optical fiber cable,
Place the interface in a non-explosion-proof area and place the phone in an explosion-proof area! ! do. The electric mm is provided with a first light emitting element and a first light receiving element for transmitting a transmission/reception signal via an optical fiber cable. On the other hand, the interface is configured to be provided with a second light emitting element and a light receiving element for receiving one transmission/reception signal via an optical fiber cable.

The above-mentioned objects and other objects and features of the present invention will become clear from the following description of embodiments with reference to the drawings.

Embodiment of the Invention FIG. 1 is a schematic block diagram of an embodiment of the invention. First, an overview of the present invention will be explained with reference to FIG. An interface 40 is connected to the exchange 10, and a 112 channel 41N20 is connected to this interface 40 via an optical fiber cable 80. The interface 40 is lj! in a non-explosion-proof area. Stomach and call 1
1i20 is placed in an explosion-proof area. Interface 4
0 is for converting a transmission/reception signal given from the outside via the exchange 10 and transmitting the optical signal to the telephone set 20 via the optical fiber cable 80. Note that the interface 40 is provided with a detector that detects a call signal given from the outside via the exchange mio, and the call lamp 101 is turned on in response to this detection signal.

The call lamp 101 is provided, for example, in a non-explosion-proof area near an interface separated by a wall from the explosion-proof area where the telephone 20 is installed. The light from this call lamp 101 is guided to an explosion-proof area by a bundle light guide 103 formed by bundling a large number of optical mi, and a display 102 in the explosion-proof area indicates that there is a call.

A plurality of indicators 10 are distributed by branching the end of the bundle light guide 103 placed on the explosion-proof area side.
The call may be displayed at 2.

Further, as the display 102, various display devices such as a display that lights up a display lamp or displays characters representing a call based on the detection output of the call signal can be considered.

FIG. 2 is an external view of a telephone included in one embodiment of the present invention. Referring to FIG. 2, a telephone 20 includes a main body 21, a dial full 22, and a handset 23, similar to a conventional telephone. However, this telephone 20 is connected to the interface 40 by an optical fiber cable 80.

FIG. 3 is a concrete block diagram of the telephone 2O. In this configuration, an optical receiving signal provided from the interface 40 via the optical fiber cable 80 is transmitted to the light receiving element 24.
is input. The light-receiving element 24 is composed of, for example, a photodiode or a phototransistor.

The optical reception signal is then converted into an electrical signal by the light receiving element 24, and is applied to the amplifier 25, where it is amplified. The output of this amplifier 25 is given to a filter 26. The filter 26 is for removing noise etc. from the output of the amplifier 25. The output signal of the filter 26 is sent to the hook switch 2
7 to the handset 23 via contact 28. This hook switch 27 closes the contacts 28 to 30 when the handset 23 is picked up from the main body 21. When the contact 30 of the hook switch 27 is closed, an oscillation signal of frequency f2 is applied from the oscillator 31 to the filter 32 as a call detection signal.

This oscillation signal f2 indicates that the handset 23 is taken up from the main body 21 and the hook switch 27 is closed. The oscillator 35 provides an oscillation signal of frequency f1 to the dial 22. Then, when the dial 22 is turned, the oscillation signal f1 is given to the modulator 36 only while the dial 22 is turning, and the dial pulse f1
' is provided to the modulator 36. The modulator 36 modulates the oscillation signal f1 with a dial pulse f1'. This modulated signal is applied to filter 32.

Note that the filter 32 is connected to the transmitting/receiving voice n23 via the contact 29.
A transmitting signal is given from

The filter 32 receives a transmission signal, an oscillation signal f2, and a modulation signal f1.
+f1'. The output signal of filter 32 is given to modulator 33.

The modulator 33 is for modulating the aforementioned three signals into optical signals. The output signal of the converter II 33 is then given to the light emitting element 34 and converted into an optical signal. This light emitting element 34 is, for example, a light emitting diode (LED). Furthermore, a connector 37 is provided that receives the DC power +12V supplied from the interface 40. This DC power supply +12V is connected to amplifier 25 and oscillator 31.3.
5 and modulators 33 and 36, but this DC power supply +12V is not supplied from the interface 40 (it is also possible to have a built-in battery inside the telephone 20. Also, the power cable connecting the interface 40 and the telephone 1M20 can be omitted.

FIG. 4 is a concrete block diagram of the interface 40. In the configuration, input terminals L1 and L2 are exchanged a1
0, and can detect calling signals and outgoing/receiving signals from outside. When a call signal is input, capacitor 6
A current flows through the relay 69 and the coil 70 as a calling signal detection means. Accordingly, the contact 71 is engaged.

The contact 71 is also S when connected to the connector 72, and this connector 72 is connected to the call lamp 1 explained in FIG.
01 is connected, and the light from the call lamp passes through the bundle light guide i03 to the indicator 10 placed in the prevention I@ area.
The call is displayed in 2.

The light receiving element 41 is given a signal [2 indicating that the knock switch 27 is closed, a dial signal fl+fl-, and a transmitting signal from the electric &1ta 20. Light receiving element 41
is composed of, for example, a photodiode or a phototransistor, and converts the input optical signal into an electrical signal. This signal is amplified by an amplifier 42 and given to a filter 43.
This is for separating the dial signal r1+f1- and the transmission signal, respectively. Oscillator @f2t yo con/ru-
data 44.

The comparator 44 determines whether the input signal is the oscillation signal f2 or not, and if it is the call detection signal f2, it provides a signal to the driver 45. The driver 45 drives the coil 47 of the relay 46. relay 4
When coil 47 of No. 6 is driven, contacts 48 and 49 are closed. Further, the dial signal r1+ is output from the filter 43.
r1- is applied to amplifier 50.

The amplifier 50 amplifies the input signal and sends it to the comparator 5.
1 and 56. The combiner 51 detects the dial pulse f1 from the dial signal fl+f1-.

When the comparator 51 detects the dial pulse f1,
The detection signal is given to the driver 52. The driver 52 intermittently controls the coil 54 of the relay 53 based on dial pulses. When the coil 54 is controlled intermittently, its contacts 55 open and close a number of times depending on the number of dial pulses.

Therefore, depending on the opening and closing of the contact 55, the terminals L1 and L
2 sends a dial pulse to the exchange 10.

The comparator 56 receives a signal @f1' corresponding to the period in which the dial 22 is being turned from the dial signal riot1'.
This is to detect. This period signal f1- is given to the driver 57. The driver 57 drives the coil 59 of the relay 58 based on the period signal f1-. coil 59
When is driven, contact 6O is closed. That is, when contact 60 is closed, transformer 62 . The communication circuit constituted by the OR circuit 64, the capacitor 65, and the variable resistor 66 is short-circuited. The purpose of short-circuiting the telephone circuit in this manner is to prevent dial pulses caused by opening and closing of contacts 55 of relay 58 from being sent to telephone 1120 via the telephone circuit.

This call circuit uses the same telephone 20 as the transmitting signal of the telephone 20.
This prevents the incoming call from going to the other end of the line, and provides only the outgoing call signal from the other party input via the exchange 10 to the driver 67. The driver 67 activates the light emitting element 68 based on the transmitting signal.
to drive. This light emitting element 68 is constituted by, for example, a light emitting diode (LED).

Furthermore, the interface 40 has an AC power supply Δciooo
A connector 73 is provided for receiving v. A power supply circuit 74 is connected to this connector 73. This i source circuit 74 is an amplifier 42.5 included in the interface 4O.
0.61 and =J There is a line for supplying DC voltage to the inverter 44, 51, 56 and driver 45, 52, 57, 67, as well as supplying the telephone 20 with a DC voltage of +12V. A connector 75 is provided to supply the telephone 20 with a DC voltage of +12V. Please note that the telephone number is $1.
When the 120 is powered by a battery, the connector 7
5 is omitted.

FIG. 5 is an external view showing an example of the optical fiber cable 80, in particular, FIG.
Figure (b) shows a side view. Referring to FIG. 5, optical fiber cable 80 includes a pair of optical fibers 82 and 83, and in order to protect these optical fibers 82 and 83,
A tension member 81 is provided approximately at the center thereof.

Optical fibers 82 and 83 are covered by nylon jackets 84 and 85, respectively. Furthermore, Tyrongi 11 butts 84 and 85 have Kevlar braids 86 and 8, respectively.
7 and k. Zarani, Ri “Bra Braid 8
6 and 87 are covered with polyethylene coatings 88 and 89. Then, polyethylene coatings 88 and 89 and tension member No. 81 are covered with PV''C nylon coating 90.
It is integrated with the Nyotsu-C and is roughly covered with an Ajiro exterior 91. Note that from the interface 40 to the telephone 20
When supplying a DC voltage of 12V to
, 931 (not shown) are provided.

FIGS. 6 and 7 are waveform diagrams for explaining the specific operation of an embodiment of the present invention.

Next, with reference to FIGS. 1 to 81!7, the concrete operation of one embodiment of the present invention will be described.

First, when calling an external telephone from the telephone 20,
Pick up the handset 23 from the main body 21. Then, the contact 28 of the hook switch 27 is closed, and the oscillation signal f2 of the oscillator 31 is applied to the ink face 40. This oscillation signal is detected by a comparator 44.

Then, the driver 45 drives the coil 47 of the relay 46. Contacts 48, 49 are thereby closed and the line is connected.

Next, by turning the dial 22, the oscillation signal f of the oscillator 35 is
A signal f1- and a dial pulse f'1 corresponding to the period in which the dial is being rotated based on 1 is applied to the modulator 36. The modulator 36 modulates the oscillation signal r1 based on the dial pulse and outputs a dial signal f1+f1''.

This dial signal r1+ri- is applied to the filter 32° modulator 332 light emitting element 31!1. It is provided to interface 40 via fiber optic cable 80 .

At the interface 40, the dial signal fl+f1' is separated by a filter 43 and applied to an amplifier 50. Then, the comparator 56 detects the period signal f1'', and the driver 57 drives the relay 58. As a result, the contact 6O is closed and the communication circuit is short-circuited.

On the other hand, comparator 51 detects dial pulse t1, and driver 52 drives relay 53.

When the relay 53 is driven, its contact 55 is opened/closed and a dial pulse is sent to the outside via the alternating current FAl 1110. When the driver 57 loses the period signal, the relay 5
8 is stopped and its contact 60 is opened. By closing the contact 60, the short circuit state of the communication circuit is released.

The transmit signal sent from the handset 23 is applied to the filter 32 via the contact 29 and sent to the interface 40.

In the interface 40, the transmitting signal is separated by a filter 43, and the transmitting signal is applied to the communication circuit via an amplifier 61. This transmission signal is transmitted from the communication circuit to contact 48.
．． 49 to the exchange 10. Conversely, a reception signal from the other party is sent from the exchange 10 to the communication circuit via contacts 48 and 49. Then, the driver 67 drives the light emitting element 68 based on the reception signal, and provides the optical reception signal to the light receiving element 24 via the optical fiber cable 8O.

The light receiving element 24 converts the pre-received word signal into an electrical signal, and the amplifier 25 . Filter 26. Handset 2 via contact 28
Give to 3. In this way, calls are transmitted and received between the telephone 20 and the outside.

Next, when the telephone 20 is called from the outside, the relay 70 of the interface 40 is driven based on the calling signal.

When the relay 70 is driven, its contacts 71 are closed and the call lamp 101 lights up, and the light from this lighting is transmitted to the display 102 via the bundle light guide 103, and the display 102 displays a call display. Let's do it.

When the handset 23 of the telephone 2o is picked up from the main body 21 in response to this call display, the contacts 28 to 30 of the hook 27
is closed. Then, the oscillation signal f2 is given from the oscillator 31 to the interface 4o. The comparator 44 of the interface 4o detects the oscillation signal "2", and the driver 45 drives the relay 46 accordingly.

When the relay 46 is activated, the contacts 48 and 49 are closed and the line is connected. Thereafter, in the same manner as described above, it becomes possible to send and receive calls between the telephone 1m20 and the outside.

As described above, according to this embodiment, the relay 69 detects a calling signal from the outside, and the relay 46 connects the line as an intermittent part of the DC signal between the telephone and the exchange.
and relay 5 for sending dial pulses to the outside
3 etc. are built into the interface 4O placed in the non-explosion-proof area, and the telephone 20 placed in the explosion-proof area does not have a built-in call bell, so that the telephone 20 does not generate sparks.

Moreover, in order to notify a call from the outside, a call lamp 101 placed in a non-explosion-proof area is lit, and the light from this lighting is transmitted through a bundle light guide 103 to a nearby telephone 120 placed in an explosion-proof area. Display device 102 provided in
By guiding the explosion, the risk of explosion can be completely prevented.

In the above-described embodiment, the present invention is applied to a dial-type telephone 2O, but the present invention is not limited to this, and a button-type telephone may be used.

Effects of the Invention As described above, according to the present invention, the interface is placed in a non-explosion-proof area, the telephone is placed in an explosion-proof area, the two are connected by an optical fiber cable, and the telephone is provided with a calling bell. Since the interface detects a call without any interference, there is no chance of sparks from the telephone that could cause an explosion. Therefore, even in dangerous places such as coal mines and ships filled with gas that may cause an explosion, it is possible to make telephone calls with the outside world using the telephone.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of one embodiment of the present invention. FIG. 2 is an external view of a telephone included in one embodiment of the present invention. FIG. 3 is a concrete block diagram of the telephone. FIG. 4 is a concrete block diagram of the interface. FIG. 5 is a diagram showing an example of an optical fiber cable. FIGS. 6 and 7 are waveform diagrams for explaining the specific operation of an embodiment of the present invention. In the figure, 10 is an exchange, 2o is a telephone, 22 is a dial, 23 is a handset, 24 is a light receiving element, 25 is an amplifier, 27 is a hook switch, 31.35 is an oscillator, 33.
36 is a modulator, 34 is a light emitting element, 40 is an interface, 41 is a light receiving element, 42, 50, 61 is an amplifier, 43
is a filter, 44.51.56 is a comparator, 46.
53, 58 is a relay, 60 is a light emitting element, 8o is an optical fiber cable, 101 is a call lamp, 102 is an indicator,
103 indicates a bundle light guide. Patent applicant: Dainichi Nippon Electric Cable Co., Ltd. (2 idiots) Procedural amendment dated February 14, 1980 2, Name of invention Explosion-proof telephone device 3, Relationship to the person making the amendment Case Patent applicant address: Amagasaki, Hyogo Prefecture Name of No. 8 Nishinocho, Higashimukojima, City (326
) Dainichi Nippon Electric Cable Co., Ltd. Representative Yukio Aoyama (
(and 1 other person) 4. Agent Address: Yachiyo Daiichi Building, 2-3-9 Tenjinbashi, Kita-ku, Osaka, Japan Voluntary amendment 6. Figures '1 and 2 of the drawings subject to amendment. 7. The contents of the 71st envelope are as shown in the attached sheet. Jsu top

Claims (1)

[Scope of Claims] An explosion-proof telephone device in which an interface connected to an exchange is placed in a non-explosion-proof area, a telephone is placed in an explosion-proof area, and the interface and the telephone are connected by a pair of optical fiber cables. When hot, the telephone set includes a handset, a first light receiving element coupled to one end of one optical fiber cable to convert an optical reception signal provided from the interface into an electrical signal, and the other optical fiber cable. a first light emitting element coupled to one end of the fiber optic cable for converting a transmission signal provided from the handset into an optical signal, the interface coupled to the other end of the one optical fiber cable; a second light emitting element that converts a reception signal given through the exchange into an optical signal; and a second light emitting element coupled to the other end of the other optical fiber cable, which converts an optical transmission signal given from the telephone into an electrical signal. an explosion-proof telephone device comprising: a second light-receiving element applied to the exchange via the exchange; and a ring signal detection means for detecting a ring signal applied via the exchange; A call lamp placed in the area is lit, and the light from the lamp is guided to the explosion-proof area using a bundle light guide.
An explosion-proof telephone device characterized by displaying a call.