JPH0811670B2 - Elevator power supply detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a power supply detection device in an elevator control device.

(Prior Art) In recent years, the widespread use of microcomputers has been remarkable, and in combination with the price reduction thereof, microcomputers have come to be applied to all kinds of social devices. Among them, microcomputers have been applied to control devices relatively early on, and are now being used in the most important systems.

Furthermore, it has become common to install a plurality of microcomputers in a system as needed. Microcomputers are also used in elevator control devices, and in recent systems, they are used for various purposes such as elevator sequence control, safety protection circuits, and motor control circuits.

Now, in a control system in which a plurality of microcomputer circuits are provided in this way, since the functions and applications of the devices equipped with the respective microcomputers are defined,
It is necessary to exchange the processed signals. Although there are various signal exchange methods, a current drive parallel transmission method is generally used for particularly important signals such as serial transmission and network transmission.

In the case of such a parallel transmission system, the power supply of the transmission circuit and the power supply of the microcomputer for processing data are separate systems. Therefore, conventionally, in a system having a plurality of such power supplies, a power supply detection circuit is provided and a processing circuit that detects and processes an abnormality in the power supply is used.

FIG. 4 is a block diagram showing a schematic configuration of a general elevator control device. In FIG. 1, a power supply circuit 2 connected to an external power supply 1 supplies regulated power to each of the microcomputers 4 and 5 and the power supply control circuit 6 via a power supply line 3. Microcomputer 4,
5 and the electric control circuit, the signal transmission line 11a, 11
It is performed via b, 12a, 12b. Further, a predetermined power is supplied from the power supply circuit 2 to the signal transmission system constituted by these signal transmission lines 11a, 11b, 12a, 12b through the transmission circuit power supply line 10.

A control signal for controlling the elevator car 8 is read from the call input circuit 9 into the microcomputer 4, subjected to predetermined processing via the microcomputer 5 and the electric motor control circuit 6, and the processed signal is transmitted to the hoisting machine 7. Then, the elevator car 8 is controlled.

Next, the operation of such an elevator control device will be briefly described. The power of the external power supply 1 is input to the power supply circuit 2, and the power supply circuit 2 supplies a predetermined voltage to each part of the elevator control device through the power supply line 3.

A command from the call input circuit is input to the first microcomputer 4, and signals such as an operation command and a direction command are input to the second microcomputer 5 via the signal transmission line 11a. The second microcomputer 5 confirms the signal of the safety circuit and sends the final operation command signal to the electric motor control circuit 6 via the signal transmission line 12a. The electric motor control circuit 6 controls the electric motor to operate the hoisting machine 7. The elevator car 8 is driven to a predetermined floor via the car.

Next, the transmission circuit between the microcomputers 4 and 5 will be described in more detail.

FIG. 5 shows a transmission circuit between the microcomputers 4 and 5,
3 is a circuit diagram showing a connection relationship with the power supply circuit 2. FIG. The power supply circuit 2 to which power is input from the external power supply 1 includes a power supply circuit 14 for supplying power to the microcomputers 4 and 5.
It is composed of a power supply circuit 15 for supplying power to the transmission circuit. The microcomputer 4 has a sequence control function, and particularly in an elevator, detection of door opening / closing is an important control.
In other words, if the door should open during driving, it could lead to a serious accident.Therefore, a signal of the open / closed state of the door is input, and if the door is opened when the speed of the elevator is open, this is detected. To stop passengers and protect passengers.

A door open detection circuit 16 in the call input circuit detects the open / closed state of the door, and a signal from this door open detection circuit 16 is transmitted to the microcomputer 4 to perform a predetermined sequence control in response to the door open detection signal. Is input to the microcomputer circuit 17 for performing. Microcomputer circuit
At 17, the speed signal is compared with the signal from the door, and when the door is opened during traveling, a door open traveling signal is sent to the second microcomputer 5 via the signal transmission line 19 to activate the protection circuit. Then, in a normal state, the transistor output circuit 18 is turned on by a command from the microcomputer circuit 17.

Therefore, the potential of the door open abnormality detection terminal 20 becomes the same potential as the power supply line 21, so that a current flows through the input resistor 22 and the photocoupler 23 is turned on. However, when the door is opened while the elevator car is running, the transistor output circuit 18 is turned off and the protection signal output from the photocoupler 23 is turned off. Detected via 24, the protection circuit is activated and the protection operation is performed according to the elevator situation.

The operation of the door protection circuit has been described above. Next, the operation when a temporary power failure or voltage drop occurs due to some cause such as lightning strike or typhoon will be described.

At this time, the input voltage of the power supply circuits 14 and 15 drops due to the voltage drop of the external power supply 1 or the occurrence of a power failure or the like. Therefore, the output voltage also drops. In general, the power supply circuit 2 has a longer holding time because the power supply circuit 14 for supplying power to the microcomputer requires accuracy and stability, and conversely, the power supply circuit 15 for supplying power to the transmission circuit. Is designed to have a relatively short retention time.

Further, even when the circuits are designed using the same circuit, the holding time is not always the same due to variations in capacitors and other parts. For this reason microcomputer
The transmission circuit power may be turned off even if 4,5 are operating.

At such a time, a power supply detection circuit is provided to detect that signal transmission is not normal. That is,
The positive side power supply line 10A of the power supply circuit 15 is connected to the positive side transmission power supply terminals 26 and 27 of the microcomputer 5 and the negative side power supply line 10B is connected to the negative side transmission power supply terminal 28 to configure the power supply detection circuit. Has been done.

Further, the negative power supply line 10B is the power line 2 of the transmission signal line.
Connected with 1. Further, in the microcomputer 5, it is connected to the terminal 27 via a resistor 29 and a photocoupler 30.

Next, the operation when the power supply is lowered will be described. Since the voltage between the positive power supply line 10A and the negative power supply line 10B decreases due to the voltage decrease, the input signal to the photocoupler 30 is turned off. Therefore, the signal indicating the abnormality of the transmission power source is input to the processing circuit 25 via the power source detection signal input terminal 31. The processing circuit 25 performs processing that is not considered abnormal even if an abnormal signal for a certain period of time is detected. However, since the positive power supply line 10A is also used as the power source of the above-described abnormality detection circuit, the decrease in the power is input from the positive transmission terminal 26 of the abnormality detection circuit and turns off the input signal to the photocoupler 23.

Therefore, the protection signal originally transmitted from the photocoupler 25 is turned off, and the protection signal input terminal 24 is in a state of detecting an abnormality.

Here, if the processing circuit 25 has already detected the decrease in the power supply by the above-mentioned power supply detection circuit, no malfunction occurs. However, if the power supply detection is delayed due to the delay in the operation of the two input circuits, the abnormality detection state is set.

However, it is not a true abnormality such as opening a door while the elevator is running, but a cause due to a power failure due to a power outage or the like is mistakenly detected as an elevator abnormality, and the protection circuit may be activated unnecessarily. there were. When such a situation occurs, the passengers of the elevator may be anxious.

(Problems to be Solved by the Invention) As described above, in the conventional elevator power supply detection device, when a power supply abnormality occurs, it is determined that this power supply abnormality is an abnormal signal during traveling of the elevator, and a protection operation for coping with the abnormality is performed. There was a problem that it would occur.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide an elevator power supply detection device that does not inconvenience passengers and managers without taking unnecessary protective measures against power supply abnormalities.

[Structure of Invention]

(Means for Solving Problems) The present invention provides a signal transmission between a plurality of microcomputers including a processing circuit that performs a protection operation for responding to an abnormality in an elevator in response to the protection signal indicating the abnormality. In the elevator power supply detection device, which is connected to a power supply circuit that supplies power to a signal transmission system to be controlled, and supplies a transmission power supply abnormal signal to the processing circuit when the power supplied to the signal transmission system is abnormal, the transmission The present invention is characterized in that means is provided for temporarily interrupting the start of the protection operation when an abnormal power supply signal is generated and performing an interrupt process in the processing circuit to cope with an abnormal power supply.

(Operation) When the transmission power supply is abnormal, the start of the protection operation is temporarily suspended and interrupt processing is performed to handle the transmission power supply abnormality. As a result, the microcomputer can promptly know that the power supply has dropped, so that it is possible to prohibit the protection operation processing in response to the protection signal transmitted subsequently.

Therefore, the malfunction of the protection operation due to the power supply voltage drop is prevented.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of the present invention. Fifth
The same parts as those of the conventional circuit shown in the figure are designated by the same reference numerals, and the description thereof will be omitted.

In the circuit according to the present invention, the protection signal delay circuit 32 is inserted between the output side of the photocoupler 23 and the protection signal input terminal 24.

Further, as a power supply detection terminal of the processing circuit 25, a power supply detection signal interrupt input terminal 33 is provided in addition to the power supply detection signal input terminal 31 for detecting a power supply abnormality of a normal transmission circuit power supply.

When the power supply voltage decreases and the transmission circuit power decreases, the input signals flowing to the transmission power supply terminals 26 and 27 to the microcomputer 5 and the insulating photocouplers 23 and 30 are turned off at substantially the same time. The input order of the input signals is indefinite due to variations in circuit constants and the like. The power supply detection signal is transmitted from the output of the photocoupler 30 to the interrupt input terminal 33 of the processing circuit 25.

It is also input to the normal input terminal 31 and is read and processed by the processing circuit 25 at a predetermined cycle. When the power supply voltage drops due to lightning or other reasons, an interrupt is issued to notify the processing circuit 25 as soon as possible, and normal processing is interrupted to prepare for power supply drop. That is, the processing circuit 25 can promptly know the power drop by executing the interrupt processing routine started by the interrupt input of the power drop signal.

On the other hand, the protection signal sent from another microcomputer through the door open abnormality detection terminal 20 is detected even though the microcomputer is not operating because the input of the photocoupler 23 is turned off due to the decrease of the power supply. Then, the signal arrives at the protection signal input terminal 24 of the protection circuit 25 via the photo coupler 23 by the protection signal delay circuit 32 with a certain delay.

In the case of the conventional apparatus, the protection signal is erroneously detected by this processing routine, and thus the protective operation such as the sudden stop of the elevator is working.However, in the case of the present embodiment, the power detection of the power source is detected before this signal is input. Routine processing for prohibiting the protection operation processing is performed by the interrupt routine, so that malfunction of the protection operation is prevented.

2 (a) and 2 (b) show a flowchart in the microcomputer processing according to the present invention.

Elevator control processing (step 101) is performed after initialization, and then the protective operation routine (step 106 and subsequent steps) is entered. When this routine ends, return to the elevator control processing (step 101) again. Is configured.

When interrupt processing is detected during the elevator control processing, the interrupt processing start routine (step 102) is started.

In this interrupt processing routine, the power down flag is set (step 103) and the power down timer is started (step 104). When the interrupt processing is completed (step 105), the original processing is returned to.

After that, the protection operation routine is entered (step 106),
Check for low power flag (step 10
7) If this is on, the power down timer is further checked (step 108).

Further, if the timer has not passed a certain period of time, the process returns to the elevator control process (step 101), and if the certain period of time has passed (step 109), the power supply low flag is cleared (step 110) and the elevator control process (step 101).
Then, in the next routine, the above-mentioned power supply drop line is checked to proceed to the off side, that is, the routine in which the power supply is normal. That is, if the timer does not elapse for a certain time, the check is repeated until the timer reaches the certain time.

On the other hand, when the low power supply flag is off, that is, when the power supply is normal (step 107), a protection signal is input (step 111), and a protection operation such as stopping the elevator is performed depending on the status of the protection signal (step 112). That is, the interrupt processing routine prohibits the input of the protection signal for a certain time, and the malfunction is prevented by passing the protection processing routine.

FIG. 3 is a time chart of various signals (door open abnormality detection signal S34, power supply detection signal S41, door open abnormality detection delay signal S42, interrupt processing period signal S35) generated when the power is abnormal.

The power detection signal S41 is input to the power detection signal input terminal 31,
The door open abnormality detection signal S34 is detected by the detection terminal 20, and the door open abnormality detection delay signal S42 is detected by the protection signal input terminal 24.

In this time chart, the door open abnormality detection signal S34
Shows the case where is detected earlier than the power supply detection signal S41 by the period 36. However, even in such a case, the processing circuit 25 is delayed by the period 37 from the detection due to the function of the protection signal delay circuit 32.
Since the door open abnormality is detected during
It is entered with a delay of 38.

Further, the interruption processing performs the malfunction prevention processing at the same time as the power detection, and the malfunction is prevented until the malfunction prevention margin time 40 elapses from the power restoration time 39, so that the malfunction does not occur until the abnormal signal disappears completely.

〔The invention's effect〕

As described in detail with reference to the embodiments above, the present invention detects an abnormality of the transmission power supply provided with the interrupt processing routine as soon as possible and temporarily holds the protection signal even if a protection signal is generated due to a malfunction and interrupts. Since the processing is performed, it is possible to prevent an erroneous protection operation due to a transmission power supply abnormality.

Therefore, there is an excellent effect that it is possible to ensure the operation of the elevator that does not disturb passengers and managers.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a flow chart for explaining the operation of the embodiment, FIG. 3 is a time chart of various signals generated when a power supply is abnormal, and FIG.
FIG. 5 is a block diagram showing a schematic configuration of a general elevator control device, and FIG. 5 is a circuit diagram showing a transmission circuit portion of a conventional power supply detection device. 14,15 ... Power supply circuit, 24 ... Protection signal input terminal, 25
…… Processing circuit, 31 …… Power detection signal input terminal, 32 …… Protection signal delay circuit, 33 …… Power detection signal interrupt input terminal,
34: Door open abnormality detection signal.

Claims (1)

[Claims] 1. A plurality of microcomputers including a processing circuit that performs a protection operation for coping with an abnormality in response to a protection signal indicating an abnormality of an elevator, and a signal transmission system that controls signal transmission between these microcomputers. In an elevator power supply detection device that is connected to a power supply circuit that supplies power and that supplies a transmission power supply abnormality signal to the processing circuit when the power supply supplied to the signal transmission system is abnormal, the transmission power supply abnormality signal is output when the transmission power supply abnormality signal is generated. An elevator power source detection device comprising means for temporarily interrupting the start of a protection operation and performing an interrupt process for dealing with an abnormality in a transmission power source in the processing circuit.