JPH0312793Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an improvement of a safety device for an elevator.

[Conventional technology]

Generally, the elevator landing door has a lock switch,
A door switch is provided on the car door to form a safety circuit so that the elevator car cannot be moved up or down unless the car door and all landing doors are closed.

That is, as shown in Figure 2, for example, in a five-story building, the lock switches DS from the first floor to the fifth floor are
There is an independent series circuit for 1 to DS5 and a circuit for door switch GS, and if all the hall doors are closed, relay RY1 is energized through lock switches DS1 to DS5, and if the car door is closed, the door switch is energized.
Relay RY2 is energized through GS, and relay RY
If both 1 and RY2 are not energized, their contacts
Electric power is not supplied to the known elevator drive device 10 through RY1a and RY2a.

[Problem that the invention attempts to solve]

However, in such a conventional device, if a fault occurs in an open state in the door switch or lock switch, the circuit becomes a fail-safe circuit that does not supply power to the elevator drive device 10, but if any one of the switches fails in a short-circuit state, it becomes a fail-safe circuit. In this case, even when power is supplied to the elevator drive device 10 and the door is open, the elevator car may move up and down, which is extremely dangerous.

The present invention has been developed in view of the above points, and it is an object of the present invention to provide a safety device for an elevator that is fail-safe even if a short-circuit failure occurs in a door switch or a lock switch.

[Means for solving problems]

The present invention includes a first detection means for detecting whether the elevator landing door is closed by a lock switch, and a second detection means for detecting whether the elevator car door is closed by the door switch. and which enables the elevator to operate when the first detection means and the second detection means detect the closing of the hall door and the car door, An abnormality detection device is provided that detects an abnormality when only either the detection means or the second detection means detects the closing of the door for a predetermined period of time or more, and when the abnormality detection device detects the abnormality. This prohibits the operation of the elevator.

[Effect]

With the above structure, if a failure such as a welding phenomenon occurs in the lock switch or door switch, the opening/closing operations of the lock switch and door switch will be out of synchronization, and an abnormality will be detected.

The device of the present invention will be described below with reference to the drawings.

〔Example〕

Figure 1 is a circuit diagram of one implementation of the present invention, and in the figure E
+, E- are power bus lines, RY1c is the relay in Figure 1
The normally open contact of RY1, RY1b is the normally closed contact of relay RY1, also shown in Figure 1, RY2c is the normally open contact of relay RY2, also shown in Figure 1, RY2b is the normally closed contact of relay RY2, also shown in Figure 1, and RY3 is the voltage The safety relay of this invention is energized when the voltage is applied.
RY3a is the normally open contact, RYa is the relay contact that closes when the elevator is operated even if the car door is open during emergency operation such as during a fire, for example during secondary firefighting operation, R is the resistance, and C is the contact. This RC capacitor provides relay RY3 with a slight time-limited return function.

In such a circuit, during normal elevator operation, the car door and one of the landing doors always open and close in conjunction with each other, so relays RY1 and RY2 repeat energization and deenergization in approximately synchronization, so that the door When opening and closing, "E+-RY1b-RY2b-RY3-E
−”, and when closed, “E+−RY2c−”
RY1c-RY3-E-", relay RY3 is always energized (relays RY1 and RY2 are energized by the RC circuit for a predetermined period of time even if they are not completely synchronized).
RY3 is kept energized), and like the conventional device, the closed circuit "E+-RY1a-RY2a-RY" is closed only when the car door and all landing doors are completely closed.
3a-10-E" elevator drive device 1
Electric power is supplied to 0 and the elevator car can be operated.

However, even though the car door and the landing door are interlocked, if at least one of the lock switches DS1 to DS5 or the door switch GS is separated into open and closed circuits due to a failure, that is, even if the door is open, Relays RY1 and RY2 are energized and deenergized when the contacts are closed regardless of the situation (this is more dangerous in terms of failure), or when the contacts are open even though the door is closed. As a result, relay RY3 is deenergized and an abnormality is immediately detected, and since contact RY3a is opened, power is not supplied to elevator drive device 10 and the elevator car does not move up or down.

Furthermore, once the relay RY3 is deenergized and an abnormality is detected, safety can be further enhanced by preventing the elevator car from going up or down unless the return button is pressed after the cause is investigated. FIG. 3 shows an implementation circuit diagram in this case. Figures 1 and 2 in the diagram
Items with the same reference numerals as those in the figure indicate the same items.
TRY is an operation delay relay that operates after a predetermined time when voltage is applied, TRYb is its time-limited normally closed contact, RY3c is the normally open contact of relay RY3, and BS is a return button, that is, when the power supplies E+ and E- When the power is turned on, the closed circuit “E+-RY1b-RY2b-TRYb
-RY3-E-” or “E+-RY2c-RY
1c-TRYb-RY3-E-” relay RY
3 is energized and its contact RY3c is closed and the contact TRYb is opened after a predetermined period of time during which it can maintain itself.
2 becomes out of synchronization and relay RY3 is deenergized, contact RY3c of relay RY3 is open, so relay RY3 will be energized unless you press the return button BS or turn on the power again. The elevator car can be configured so that the elevator car cannot be raised or lowered without being moved.

In the above explanation, each detection device has an output contact for operating a relay sequence. The present invention is not limited to the embodiments.

[Effect of idea]

As described above, according to the present invention, it is checked whether the opening and closing operations of the landing door and the car door are always synchronized, and if they are not synchronized, it is determined that there is an abnormality. It is possible to obtain a safety device that always serves as a fail-safe circuit even in the event of such a failure, thereby increasing safety.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of one embodiment of the present invention, FIG. 2 is a conventional safety circuit diagram, and FIG. 3 is a circuit diagram of another embodiment of the present invention. DS1 to DS5...Lock switch, GS...Door switch, RY1...Relay (first detection means),
RY2...Relay (second detection means), RY3...
Relay (abnormality detection device).

Claims (1)

[Scope of Claim for Utility Model Registration] A first detecting means for detecting whether the elevator hall door is closed by a lock switch; and a first detecting means for detecting whether the elevator car door is closed by the door switch. 2 detection means, and enables the elevator to operate when the first detection means and the second detection means detect the closing of the hall door and the car door, an abnormality detection device that detects an abnormality when a state in which only either the first detection means or the second detection means detects the closing of the door continues for a predetermined time or more; A safety device for an elevator, characterized in that when an abnormality is detected, operation of the elevator is prohibited.