JPS6361264B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a device for detecting the position of an elevator controlled using an electronic computer.

[Prior art]

In the past, many elevators have been controlled using electronic computers such as digital computers, as disclosed in, for example, Japanese Patent Laid-Open No. 160879/1983. In this case, the car position is detected by counting the pulses emitted in response to the distance the car has moved, and this car position can now be corrected by commands from the computer and external commands. There is. This is shown in FIGS. 1 to 3.

In Fig. 1, 1 is a hoisting electric motor, 2 is a driving sheave for the hoisting machine driven by the electric motor 1, and 3 is a main rope that is wound around the sheave 2 and to which a car 4 and a counterweight 5 are connected. , 6 is an endless rope with both ends connected to the car 4 and placed in the hoistway, 7 is a tension wheel provided at the bottom of the hoistway and applies downward tension to the rope 6, and 8 is an elevator machine room. A disc 9 is provided in opposition to the disc 8 and is driven by a rope 6 and has pores provided at equal intervals around the periphery; a pulse generator 9 generates a pulse each time the pores are detected; Reference numeral 10 denotes a correction switch that emits a correction signal 10a that is provided in the hoistway and is operated by a cam (not shown) installed in the car 4. Reference numeral 11 refers to a car that detects the car position by counting pulses emitted from the pulse generator 9. 12 is an electronic computer that performs call control and operation control of the elevator; 13 is a speedometer generator that is directly connected to the electric motor 1 and detects its rotational speed; 14 is a speed command generation circuit; and thyristor phase control circuit ( (none of which are shown), etc., and generates a thyristor phase control signal based on a speed command signal from an electronic computer 12, a speed feedback signal from a speedometer generator 13, etc.;
Reference numeral 5 denotes a safety circuit that issues an emergency stop signal to stop the operation of the car 4 in an emergency based on a command from the computer 12, and also includes a power failure detection circuit in the event of a power failure.
Reference numeral 16 denotes an electric motor that is composed of a brake electromagnetic contactor for the electric motor 1, a power supply electromagnetic contactor, a thyristor, etc., controls the speed of the electric motor 1 according to the phase control signal of the thyristor, and suddenly stops the electric motor 1 according to the emergency stop signal. The control device 17 is an uninterruptible power source such as a battery that supplies power to the pulse generator 9 and the car position detection circuit 11 even during a power outage.

In FIG. 2, 9a and 9b are pulse signals generated from the pulse generator 9 according to the driving direction of the car 4, 9a is an ascending pulse signal, 9b is a descending pulse signal, and 12a and 12b are described in detail later. , signals output from the computer 12, 12a is a correction data signal indicating position data to be corrected, 12b is a correction signal instructing correction, 11A is a register that stores the correction data signal 12a, and 11B is a terminal PR.
While the input to the terminal PR is "L", the current position of the car 4 is detected by counting terminal U or input pulses and the car position signal 11a is generated, and when the input to the terminal PR becomes "H", the contents are input to the terminal S. The position counter 11C that corrects the data is an OR gate that inputs the correction signals 10a and 12b and whose output side is connected to the terminal PR of the position counter 11B.

That is, when the car 4 rises, the disk 8 rotates and the pulse generator 9 generates a rise pulse signal 9 consisting of pulses emitted every unit movement distance of the car 4.
Output a. These pulses are detected by position counter 11
It is counted at B, and its contents indicate the car position. The electronic computer 12 takes in the car position signal 11a which is the output of the position counter 11B when necessary, sends it to the speed control device 14, and thereby controls the motor 1, that is, the car 4 via the motor control device 16. Speed is controlled. However, if the contents of the position counter 11B are different from the actual car position, the control of the car 4 will not be executed correctly, so the following corrective action is performed. That is, basket 4
When it reaches just before engaging the correction switch 10,
A modified data signal 12a is generated from the electronic computer 12 and stored in the register 11A. Then, the correction switch 10 operates to output the correction signal 10.
When a becomes "H", the output of the OR gate 11C also becomes "H", and the contents of the position counter 11B are corrected to the contents of the register 11A.

Now, suppose that a power outage occurs at point P shown in FIG. 3 while car 4 is running. Immediately after that, an emergency stop signal is issued from safety circuit 15, a brake is applied to electric motor 1, and car 4 is stopped. It will stop at point Q. The pulse generator 9 and the position counter 11B are supplied with the uninterruptible power supply 17 and can operate even after a power outage, and the position of the point Q should be detected correctly.

However, since the uninterruptible power supply 17 is not supplied to the computer 12 and its repeating circuit, it becomes inoperable almost immediately after a power outage, but during the transition period from the operating voltage range to the non-operating voltage range, the correction signal 1
2b and 10a emit an incorrect signal, and OR gate 11c
The output may become "H". Therefore, the contents of the position counter 11B are then changed to the register 11B.
Since the data stored in A (the state of this data is also uncertain during the transient period) will be corrected, the position of point Q may not be detected correctly. As a result, when the power is restored, the car 4 is controlled based on the contents of the position counter 11B, so even though it has reached the stop position, the computer 12 cannot determine that it has stopped, and a stop signal is generated. Problems caused by misalignment may occur, such as not being able to do so.

[Summary of the invention]

This invention is intended to improve the above-mentioned problem, and when the normal power supply fails, the car position detection circuit prevents the car position detection circuit from modifying the car position contents while the computer power supply is above the minimum operating voltage of the computer, and the normal power supply is restored. To provide a position detection device for an elevator, which can prevent a car position detection circuit from malfunctioning even if an erroneous signal is input to the car position detection circuit by canceling the blocking when the voltage exceeds the minimum operating voltage. With the goal.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 4 to 7. However, Figure 1 will be used as is.

In FIG. 4, 18 is included in the safety circuit 15 in FIG. 1, and is "L" while the normal power supply is normal, and the power supply voltage of the computer 12 is lower than the minimum operating voltage of the computer 12 during a power outage. 19 is a position counter protection circuit in the event of a power outage, and 19A is a position counter that outputs a power failure detection signal 18a that becomes "H" during a power outage. Terminal Q connected to terminal PR of device 11B
The output of the terminal becomes "H" for a certain period of time _T1 , the output of the terminal also becomes "L", and the input of the terminal R becomes "L", the output of the terminal Q becomes "L", and the output of the terminal becomes "H". The monostable element 19B is a NAND gate whose inputs are the power failure detection signal 18a and the output of the terminal of the monostable element 19A, and whose output 19Ba is connected to the terminal R of the monostable element 19A. Other than the above, it is the same as in FIG. 2.

Next, the operation of this embodiment will be explained.

First, the normal operation of the normal power supply will be explained with reference to FIG. 6A.

When the normal power supply is normal and the power failure detection signal 18a is "L", the output 19 of the NAND gate 19B
Ba becomes "H", the monostable element 19A is in an operable state, the output of the terminal Q is "L", and the output of the terminal is "H".

In step 21 of FIG. 5, the electronic computer 12 reads the car position signal 11a from the position counter 11B,
In step 22, it is determined whether the position of the car 4 is between the bottom floor and the top floor. If it is within the above range, in step 23, while car 1 is in operation, a correction signal 10 from the outside is sent.
Before car 4 arrives at the location where a is expected to be input, modified data signal 12a is output and stored in register 11A. Furthermore, if it is determined in step 22 that the position of car 4 is outside the above range,
In step 24, the car 4 is moved to the top floor or the bottom floor (details are omitted). When the car 4 reaches the top or bottom floor, the position is detected by engagement with an end point switch (not shown), and based on this, a modified data signal 12a is output and stored in the register 11A. Further, a modified signal 12b is output next to the modified data signal 12a.

Now, if the correction signal 12b from the computer 12 becomes "H" or the car 4 switches to the correction switch 10.
When the correction signal 10a becomes "H" by engaging with
The output of the OR gate 11C becomes "H". Now, the monostable element 19A operates, and the output 19a of the terminal Q becomes "H" and the output of the terminal becomes "L" for a certain period of time _T1 . When the output 19a becomes "H", the position counter 11B stops counting, the contents of the register 11A are inputted, and the contents are corrected. When the output 19a returns to "L", the position counter 11B continues counting based on the modified content. In this way, the position counter 11B is corrected by signals from the electronic computer 12 or the correction switch 10.

Next, it is assumed that a power outage occurs when the monostable element 19A is not operating, that is, when the output of the terminal is "H". Power outage detection signal 1
Since 8a becomes "H", NAND gate 19B
The output 19Ba of becomes "L", and the monostable element 19
A does not operate even if a correction signal is applied to terminal T,
No corrective operation of the position counter 11B is performed.

Next, the operation when a power outage is detected during the correction operation of the position counter 11B will be explained with reference to FIG. 6B.

When the monostable element 19A is in operation, the output 19a of the terminal Q is "H" and the output of the terminal is "L", so the output 19 of the NAND gate 19B is
Ba is "H". At this time, even if the power failure detection signal 18a becomes "H", the output 19Ba of the NAND gate 19B does not change and remains "H", so the correction operation of the position counter 11B continues. The setting time T ₁ of the monostable element 19A ends,
When the output of the terminal becomes "H", the output 19Ba of the NAND gate 19B becomes "L", and the monostable element 19A is reset. After this, even if a signal is input to the terminal T, the monostable element 19A does not operate.

Note that the time limit _T1 of the monostable element 19A is set to a value that ensures the operation of the position counter 11B, and that the power supply voltage of the computer 12 after a power failure is detected is set to a value that allows the position counter 11B to operate reliably.
The value is set to a value that is sufficiently shorter than the time it takes for the voltage to drop below the operating voltage. Therefore, even if a power failure is detected during the correction operation, the monostable element 19A is reset after the correction operation is reliably performed, that is, after the delay time _T2 has elapsed.

Therefore, after a power outage is detected, the monostable element 19A is reset while the power supply voltage of the computer 12 is equal to or higher than the minimum operating voltage of the computer 12. Even if the signal 10a generates an erroneous signal, the position counter 11B can be reliably protected.

FIG. 7 is a diagram showing the relationship from a power outage until it recovers, where a indicates the state of the power supply voltage of the computer 12, E ₁ is the normal voltage (for example, 5 V DC), and E ₂ is the state of the power supply voltage of the computer 12. The minimum operating voltage, b is the power outage period of T ₃ , T ₄ of c is the time indicating the non-operating area of the computer 12, T ₅ of d is the power outage detection period, and T ₆ of e is the protection period of the position counter 11B. shows.

〔Effect of the invention〕

As described above, the present invention modifies the contents of the elevator car position detection circuit by a command from an electronic computer or an external device, so that in the event of a power outage, the power supply voltage of the electronic computer becomes higher than the minimum operating voltage of the computer. The above-mentioned modification is prevented within a certain period of time, and the blocking of the modification operation is released after the power supply voltage of the computer reaches the minimum operating voltage of the computer upon recovery from a power outage.

This makes it possible to reliably prevent the car position detection circuit from malfunctioning during the sensitive period during a power outage.
This has the effect of preventing malfunctions in elevator operation after the power is restored. Further, even in a half-hearted case such as a momentary power outage, the same effect can be obtained.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional elevator position detection device, Fig. 2 is a block diagram of the car position detection circuit shown in Fig. 1, Fig. 3 is a car speed change curve during a power outage, and Fig. 4 is a block diagram of the car position detection circuit shown in Fig. 1. FIG. 5 is a block diagram showing an embodiment of the elevator position detection device according to the invention, FIG. 5 is a flowchart of the operation of the computer shown in FIG. 4, and FIGS. 6 and 7 are explanatory diagrams of the operation of FIG. 4. 1... Hoisting motor, 4... Elevator car, 9... Pulse generator, 10... Correction switch, 11... Car position detection circuit, 12... Electronic computer, 17... Uninterruptible power supply, 18 ...Power outage detection circuit, 19...Position counter protection circuit during power outage, 19A
. . . Monostable element, 19B . . . NAND gate. Note that the same reference numerals in the drawings indicate the same parts.

Claims (1)

[Claims] 1 A car position detection circuit operated by a normal power source and an uninterruptible power source detects the position of the car by counting pulses emitted in response to the moving distance of the car, and the signal is transmitted to a computer operated by the normal power source. The car position information of the car position detecting circuit is corrected by a command from the computer or by an external command, and the power supply voltage of the computer is changed from the power supply voltage to the computer when the normal power supply is interrupted. A power failure detection circuit that operates while the power supply voltage of the computer is above the minimum operating voltage of the computer and becomes inoperable when the power supply voltage of the computer exceeds the minimum operating voltage when the normal power supply is restored; An elevator position detection device comprising a protection circuit that prevents the detection circuit from modifying car position contents and releases the blocking when the power failure detection circuit becomes inoperable.