JP2012246073A - Elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safer elevator by carrying out a failure diagnosis in an arithmetic device at low cost and with high reliability.SOLUTION: A comparing unit 46 of the arithmetic devices 32 and 37 compares a car speed V1 calculated by using an encoder signal 28 from an encoder 21 with a car speed V2 calculated by using an acceleration sensor signal 31 from, unlike the encoder 21, an acceleration sensor 24 installed on a car 1 to detect a failure of the encoder 21 by determining whether a difference between the car speeds V1 and V2 is present in a predetermined range.

Description

  The present invention relates to an elevator equipped with a safety device that electronically realizes a protection function from a dangerous event.

  As a basic safety device in an elevator, for example, a motor that drives the main rope of the car by detecting that the car has exceeded the normal operating range by final limit switches provided at the upper and lower ends of the hoistway There is known a configuration in which a car is stopped by operating a brake provided to the vehicle or by shutting off power to a drive motor such as a hoisting machine. As another safety device, there is an emergency stop device attached to the car side. This emergency stop device is activated when the overspeed of the car is detected and grips the rail to quickly stop the car. It is configured to stop.

  As a mechanism for operating the stopping means of the car, a combination of mechanical parts such as a switch, a relay, a contactor, etc. is used from the beginning if the target is a brake operation or a power interruption, and a governor and a governor rope are used if an emergency stop device. However, in recent years, such mechanisms tend to be digitized. In an electronic safety device, a calculation device is used to calculate the input information of sensors such as switches and encoders, and when a dangerous event is detected, a signal for operating the stopping means of the car is output. Yes. With the digitalization of such safety devices, it has become possible to realize advanced safety functions such as the terminal floor forced deceleration function.

  This terminal floor forced deceleration function is a function that can variably set the upper limit of the speed of the car that operates the stopping means according to the position in the hoistway of the car. From the first upper speed limit and the first upper speed limit It is shown that a large second speed upper limit is set, the brake and power-off are activated when the car exceeds the first speed upper limit, and the emergency stop device is activated when the second speed upper limit is exceeded. (For example, refer to Patent Document 1). In addition, in order to improve the reliability of the safety device, the CPU (Central Processing Unit), which is an arithmetic device that determines the operation of the stopping means, is duplicated, and the operation results are compared and collated between the two CPUs, and the inconsistency is determined. If a car is stopped when it is detected, or the encoder provided in the governor is also duplicated to detect the car position and speed, the two encoder values are compared and verified by the arithmetic unit, and a mismatch is detected. Shows a configuration in which the car is stopped (for example, see Patent Document 2).

International Publication Number WO2004 / 076326 International Publication No. WO2005 / 049467

  However, in the conventional elevator, the encoder provided in the governor is duplicated to detect the position and speed of the car, so that the cost is increased, and the duplication of the same type of sensors causes both sensors to be damaged due to a common cause failure. There is a possibility of failure at the same time. For example, when a failure occurs such that the same type of duplicated sensors have zero output at the same time, the arithmetic unit cannot detect the failure of these sensors. In addition, if another failure occurs in a state where this failure is latent, there is a possibility that the car cannot be safely stopped.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a safer elevator by performing failure diagnosis in an arithmetic device at low cost and high reliability.

  In order to achieve the above-mentioned object, the present invention has an arithmetic device for determining abnormalities by inputting signals from a plurality of sensors for detecting the operating state of the car, and the boarding is performed based on the abnormality determination signals from the arithmetic devices. In an elevator controlling a car, an acceleration sensor is provided in the car, and the car speed is calculated by using signals from the acceleration sensor and other speed detection means different from the acceleration sensor in the arithmetic unit. A calculation unit and a comparison unit that outputs the abnormality determination signal based on a result of comparing two car speeds calculated by the calculation unit are provided.

  According to the above configuration, the comparison unit can compare the car speed V2 calculated from the acceleration sensor signal provided in the car with the car speed V1 calculated from the other speed detecting means, as in the conventional case. If the detection signal from the same type of sensor is input to the computing device, the possibility of common cause failure, which is a concern, is eliminated, and either the acceleration sensor or other speed detection means is functioning normally. You can judge whether you did it. In addition, the use of the acceleration sensor enables failure diagnosis with low cost and high reliability, and a safer elevator can be provided.

  Further, according to the present invention, in addition to the above-described configuration, the arithmetic unit stops the car when a difference between the two car speeds is larger than a predetermined value as a result of comparing the two car speeds in the comparing unit. The abnormality determination signal that is to be output is output.

  According to the above configuration, it is possible to stop the car when the difference between the two car speeds exceeds a predetermined value while preventing malfunction due to an error during speed calculation, etc. Obtainable.

  Furthermore, the present invention is characterized in that, in addition to the above-described configuration, the arithmetic unit is provided with a correction unit that resets the car speed calculated based on the value of the acceleration sensor to zero every time the car stops. And

  According to the above configuration, when the car stops, the car speed V2 obtained by the car speed calculation unit using the acceleration sensor signal acquired from the acceleration sensor is reset to zero, and other speed detection means and Even if both of the acceleration sensors are normal, it is possible to prevent accumulation of errors due to long-time integration calculation during speed calculation, and the car speed V2 obtained from the acceleration sensor is obtained from other speed detection means. Deviation from the car speed V1 can be prevented.

  In addition to the above-described configuration, the present invention further includes an offset measuring unit that measures an offset of the acceleration sensor every time the car stops. The acceleration sensor uses the offset by the offset measuring unit in the arithmetic unit. The present invention is characterized in that a car speed calculation unit for calculating the car speed is provided.

  According to the above configuration, even when the acceleration sensor is used, the car speed V2 can be accurately calculated while correcting the occurrence of the error, and when compared with the car speed V1 obtained from other speed detecting means, This can be performed with higher accuracy.

  In addition to the above-described configuration, the present invention is characterized in that the other speed detection means is an encoder.

  According to the above configuration, an encoder provided in a normal elevator can be used, and the combination with an acceleration sensor that is simpler than the encoder makes it possible to achieve reliability without complicating the overall configuration. Can be obtained.

  In addition to the above-described configuration, the present invention further includes third speed detection means different from the one that has calculated the two car speeds, and the calculation unit is configured to output signals from the acceleration sensor during the operation of the car. And a car speed calculating section for correcting the car speed calculated based on the car speed calculated based on the signal from the third speed detecting means.

  According to the above configuration, it is possible not only to prevent the car speed V2 obtained from the acceleration sensor from deviating from the car speed V1 obtained from the other speed detecting means even during the operation of the car, but the third speed detection. Since the comparison can be invalidated when a slip occurs in the means, for example, the encoder on the main rope side, a safer elevator can be provided while performing a more accurate fault diagnosis.

  Furthermore, in addition to the above-described configuration, the present invention includes a communication line that converts an output signal of the acceleration sensor provided in the car into a digital value and transmits the converted digital signal to the arithmetic device. Features.

  According to the above configuration, if the signal of the acceleration sensor is transmitted as an analog value, sufficient signal accuracy cannot be obtained due to the influence of voltage drop or noise. Even if it is long, it is possible to perform accurate control with less influence of voltage drop and noise, so that it is possible to dispose the arithmetic unit at a desired position while disposing the acceleration sensor on the car.

  According to the elevator of the present invention, the car speed is calculated by taking in the acceleration sensor provided in the car and a different sensor different from the acceleration sensor, and the car is controlled based on the difference between the car speeds. Therefore, it is possible to eliminate the possibility of common cause failure, which is a concern when the same type of sensors are duplicated, to improve the reliability of encoder failure diagnosis, and to provide a safer elevator.

1 is an overall configuration diagram of an elevator according to an embodiment of the present invention. FIG. 2 is a signal connection diagram of the elevator shown in FIG. 1. It is a functional block diagram of the arithmetic unit shown in FIG. It is a block diagram explaining the process in the arithmetic unit shown in FIG. It is a signal wiring diagram of the elevator by other embodiment of this invention. It is a functional block diagram of the arithmetic unit shown in FIG. It is a block diagram explaining the process in the arithmetic unit shown in FIG. It is a flowchart which shows the process of the arithmetic unit by the elevator by further another embodiment of this invention. It is a time chart which shows the cage | basket | car speed correction process by the elevator by further another embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall configuration diagram of an elevator according to an embodiment of the present invention. A car 1 is connected to one end of a main rope 10 and a counterweight 11 is suspended near the other end. By driving 10, the car 1 is moved up and down in the hoistway. The motor 2 is driven by the inverter 5 connected to the AC power source 7 via the energization cutoff circuit 6, and when the energization cutoff circuit 6 is activated, the power supply to the inverter 5 is interrupted. There is also provided a brake device 3 that suppresses the driving of the motor 2 and generates a braking force against the car 1. The brake device 3 is urged to a braking state in a steady state and the braking state is changed when energized. This is a configuration to be released.

  The governor rope 12 towed as the car 1 moves up and down rotates the governor 13. The governor 13 includes a gripping device 14 and an encoder 21, and when the gripping device 14 is operated, the governor rope 12 is gripped. When the car 1 is moving, the safety device 15 stops the car 1 by sandwiching the rail 16. The encoder 21 rotates with the governor 13 to generate a pulse signal, and the position of the car 1 can be obtained by integrating the amount of change of the pulse signal, and the car 1 can be obtained by calculating the time average of the amount of change. Can be determined. The car 1 is provided with an acceleration sensor 24, and the speed of the car 1 can be obtained by integrating the acceleration sensor signal. As the acceleration sensor 24, a MEMS (Micro-Electro-Mechanical Systems) sensor manufactured by applying semiconductor manufacturing technology is preferable because it is inexpensive and highly accurate.

  A buffer 17 is installed at the lower end of the hoistway, and even when the car 1 cannot be completely stopped by the braking force of the brake 3 or the emergency stop device 15, the car 1 is received and the impact is absorbed. Further, final limit switches 22 and 23 are arranged near the lower end and near the upper end of the hoistway, and these final limit switches 22 and 23 are always on, but the car 1 has these final limit switches 22. , 23 to enter the lower or upper direction, respectively, the vehicle is turned off, and the car 1 is detected as having gone too far. In the control panel near the hoistway, a control controller 25 and a safety controller 26 are provided. The control controller 25 controls the inverter 5 to operate the car 1, and the safety controller 26 includes the encoder 21 and the final controller. A dangerous event is detected by inputting the limit switches 22 and 23 and the acceleration sensor 24, and the car 1 is braked by actuating the emergency stop device 15 via the brake 3, the power cut-off circuit 6, and the gripping device 14, thereby causing the dangerous event. Try to avoid. In addition to the final limit switches 22 and 23, the elevator is provided with a number of safety switches (not shown) such as switches used for protecting maintenance personnel during maintenance.

  FIG. 2 shows a signal connection diagram of the elevator shown in FIG. The controller 25 outputs an inverter control signal 27 and controls the inverter 5. The safety controller 26 includes an arithmetic device 32 and an arithmetic device 37. Even if these arithmetic devices 32 and 37 are configured by hardware, they are ROM (Read Only Memory), RAM (Random Access Memory), digital input. Peripheral circuits such as outputs, encoder inputs, and analog inputs may be provided, and each may be constituted by a microcomputer connected to a CPU (Central Processing Unit) via an internal bus.

  The inputs of the arithmetic devices 32 and 37 are an encoder signal 28 from the encoder 21, switch signals 29 and 30 from the final limit switches 22 and 23, and an acceleration sensor signal 31 from the acceleration sensor 24.

  When the acceleration sensor signal 31 from the acceleration sensor 24 is taken into the safety controller 26, a communication interface 67 on the acceleration sensor 24 side provided on the ceiling of the car 1, and a communication interface 68 on the safety controller 26 side installed at an appropriate position, The acceleration sensor signal 31 converted into a digital value is transmitted to the arithmetic devices 32 and 37 of the safety controller 26 via the communication line 69. Although the acceleration sensor signal 31 can be taken into the safety controller 26 by other methods, since the digital signal value is transmitted to the arithmetic devices 32 and 37 using the communication line 69 in this way, the acceleration sensor is sent to the car 1. 24, the safety controller 26 is arranged at a desired position, and the signal of the acceleration sensor 24 can be transmitted without being affected by a voltage drop or noise even when the distance between the two is increased.

  On the other hand, as an output of the arithmetic unit 37, a stop request signal 33 to the AND circuit 42, a switching signal 34 to the contactor of the energization cutoff circuit 6, a switching signal 35 to the brake drive circuit 4 to energize the brake 3, This is an emergency stop operation signal 36 to the gripping device 14. Similarly, the output from the arithmetic unit 37 includes a stop request signal 38 to the AND circuit 42, a switching signal 39 to the contactor of the energization cutoff circuit 6, and a switching signal 40 to the brake drive circuit 4. 14 is an emergency stop operation signal 41. The eight output signals from these arithmetic devices 32 and 37 are stop outputs for operating the stopping means of the car 1.

  The stop request signals 33 and 38 are signals for stopping the control of the car 1 by the controller 25, which means that the signal level High is not requested and the signal level Low is requested. These signals are output to the controller 25 via the AND circuit 42. If either one of the stop request signals 33 and 38 becomes Low, the controller 25 controls the inverter 5 by the inverter control signal 27. To stop the car 1.

  The switching signals 34 and 39 are respectively supplied to two contactors connected in series in the energization cutoff circuit 6, and when the switching signals 34 and 39 are on, the contactors are switched to a connected state, and when the switching signals 34 and 39 are off, they are switched to a disconnected state. . Since the two contactors are connected in series, the energization cut-off circuit 6 cuts off the energization between the AC power supply 7 and the inverter 5 when one of the switching signals 34 and 39 is turned off.

  The switching signals 35 and 40 to the brake drive circuit 4 are respectively supplied to two contactors connected in series in the brake drive circuit 4. When the switching signals 35 and 40 are on, the contactor is in a connected state, and when it is off, the contactor is in a connected state. Is switched to the disconnected state. Since the two contactors are connected in series, when one of the signals is turned off, the brake drive circuit 4 cuts off the power supply to the brake 3 and puts the brake 3 in a braking state.

  Emergency stop actuating signals 36 and 41 are provided to the solenoid that will actuate the gripping device 14, and when both emergency stop actuating signals 36 and 41 are on, the gripping device 14 is deactivated and either one is off. In this case, the gripping device 14 is operated, and the emergency stop device 15 sandwiches the rail 16 to stop the moving car 1.

  The arithmetic devices 32 and 37 have the same configuration. Here, the arithmetic device 32 will be described with reference to the block diagram shown in FIG. The calculation device 32 includes a calculation unit 43, an input unit 44, an output unit 45, and a comparison unit 46. These functions may be configured by hardware, or may be realized by a program stored in a ROM inside or outside the microcomputer and executed by the CPU of the microcomputer.

  The input unit 44 has a function of capturing signals from each sensor, and acquires and processes the encoder signal 28, the final limit switch signals 29 and 30, the acceleration sensor signal 31, and other safety switch signals not shown. The encoder signal 28 is converted into a value indicating the speed and position of the car 1, and the final limit switch signals 29 and 30 are replaced with high on and off with low. The output unit 45 outputs a car stop signal that stops at Low as the calculation result of the calculation unit 43. The comparison unit 46 compares the car speed V1 calculated from the encoder signal 28 by the calculation unit 43 with the car speed V2 calculated from the acceleration sensor signal 31, and determines whether the difference between the two is within a predetermined range. judge.

  If the result of this determination is that it is not within the predetermined range, the comparison unit 46 determines that either the encoder 21 or the acceleration sensor 24 has failed, and an inverter 5 that stops the abnormality determination signal, for example, the car 1. Stop request signals 33 and 38, switching signals 34 and 39 to the energization cutoff circuit 6, and switching signals 35 and 40 to the brake drive circuit 4 are given to the output unit 45 so as to be on the car stop side. Although not shown, the comparison unit 46 compares the calculation result of the calculation device 37 received as described above with that of the calculation device 32, and determines whether both systems are operating normally. Similarly, when a mismatch between the two is detected, the output unit 45 is controlled so that the abnormality determination signal, for example, the car 1 is stopped.

  FIG. 4 is a block diagram illustrating an abnormality determination process performed by the calculation unit 43, and the input unit is not shown for the sake of simplicity. Here, a safety chain abnormality determination processing unit 47 and a terminal floor overspeed abnormality determination processing unit 48 are mounted. In the safety chain abnormality determination processing unit 47, any one of the safety switches including the final limit switches 22 and 23 is turned off. That is, when one of the switch signals 29 and 30 is Low, Low is output, the switching signals 34 and 35 from the output unit 45 are set Low, and the operation of the brake 3 and the energization cutoff circuit 6 is requested.

  The terminal floor overspeed abnormality determination processing unit 48 stores, as table data, a first speed upper limit curve 49 and a second speed upper limit curve 50 drawn with the position of the car 1 in the hoistway as the horizontal axis and the speed as the vertical axis. ing. The terminal floor overspeed abnormality determination processing unit 48 obtains the first speed upper limit corresponding to the position of the car 1 from the first speed upper limit curve 49, and the speed of the car 1 exceeds the first speed upper limit. , Low, and the switching signals 34 and 35 from the output unit 45 are set to Low to request the operation of the brake 3 and the power cut-off circuit 6. On the other hand, the second speed upper limit corresponding to the position of the car 1 is obtained from the second speed upper limit curve 50, and when the speed of the car 1 exceeds the second speed upper limit, Low is output from the output unit 45. The operation of the emergency stop device 15 is requested through the gripping device 14 by setting the emergency stop operation signal 36 to Low.

  Further, the calculation unit 43 uses the car position V calculated by the car position speed calculation processing unit 51 from the encoder signal 28 of the encoder 21, and the car speed calculation unit 52 calculates the acceleration sensor signal of the acceleration sensor 24. The car speed V2 obtained from 31 is input to the comparison unit 46 and compared. The processing in the comparison unit 46 using the car speed V1 and the car speed V2 determines whether or not the difference between the two is within a predetermined range as described above, and as a result of this determination, it is not within the predetermined range. In this case, the comparison unit 46 determines that either the encoder 21 or the acceleration sensor 24 has failed, an abnormality determination signal, for example, stop request signals 33 and 38 for the inverter 5 that stops the car 1, and energization interruption. The output unit 45 is controlled so that the switching signals 34 and 39 to the circuit 6 and the switching signals 35 and 40 to the brake drive circuit 4 are on the car stop side, and the occurrence of an abnormality in the arithmetic devices 32 and 37 is notified. Or On the other hand, if the difference between the two is within a predetermined range, both the arithmetic devices 32 and 37 are determined to be normal.

  According to the elevator according to the above-described embodiment, the comparison unit 46 of the calculation devices 32 and 37 is provided in the car 1, unlike the car speed V <b> 1 calculated using the encoder signal 28 from the encoder 21 and the encoder 21. The car speed V2 calculated using the acceleration sensor signal 31 from the acceleration sensor 24 is compared, and the arithmetic devices 32 and 37 operate normally depending on whether the difference between the car speeds V1 and V2 is within a predetermined range. It is judged whether it is. For this reason, it is possible to eliminate the possibility of a common cause failure, which is a concern when detection signals from the same type of sensor are input to the arithmetic unit as in the past, and the use of an acceleration sensor reduces costs and increases reliability. Therefore, it is possible to perform failure diagnosis and to provide a safer elevator.

  An encoder provided in a normal elevator can be used to calculate one car speed V1, and an acceleration sensor having a simpler configuration than the encoder can be used to calculate the other car speed V2. By using it, a highly reliable arithmetic device can be obtained without complicating the overall configuration. In addition, since the car speed V2 for comparison by the comparison unit 46 uses the acceleration sensor 24 provided in addition to the car 1, the semiconductor sensor MEMS that is less expensive than the encoder 21 is used as the acceleration sensor 24. A sensor can be used, and an inexpensive system can be realized as compared with the case where the encoder 21 is duplicated.

  Further, since the output signal of the acceleration sensor 24 provided in the car 1 is converted into a digital value and the converted digital signal is transmitted to the arithmetic devices 32 and 37 via the communication line 69, the signal of the acceleration sensor 24 is converted into an analog signal. If the value is transmitted as it is, sufficient signal accuracy cannot be obtained due to the influence of voltage drop and noise. However, when the communication line 69 is used, the arithmetic device 32 is placed at a desired position while the acceleration sensor 24 is disposed in the car 1. , 37, it is possible to perform accurate control with less influence of voltage drop and noise even when the distance between the car 1 and the arithmetic devices 32, 37 is long.

  By the way, in order to obtain the car speeds V1 and V2 from the acceleration sensor signal 31 of the acceleration sensor 24, an integral operation is performed. However, an error is accumulated in the long-time integral operation, and both the encoder 21 and the acceleration sensor 24 are normal. However, there is a possibility that the car speed V2 obtained from the acceleration sensor signal 31 deviates from the car speed V1 obtained from the encoder signal 28 and stops the elevator.

  FIG. 5 is a signal connection diagram of an elevator according to another embodiment of the present invention for solving this problem. The same components as those shown in FIG. 2 are denoted by the same reference numerals, detailed description thereof will be omitted, and differences from FIG. 2 will be described. State signals 53 and 55 indicating the current state of the power cut-off circuit 6 and state signals 54 and 56 indicating the current state of the brake drive circuit 4 are input to the arithmetic devices 32 and 37, respectively. Further, the contactor of the energization cutoff circuit 6 can be controlled not only by the switching signals 34 and 39 but also by the switching signal 57 from the control controller 25. Similarly, the contactor of the brake drive circuit 4 can be controlled only by the switching signals 35 and 40. Instead, control can be performed also by a switching signal 58 from the controller 25.

  Therefore, the brake drive circuit 4 and the energization cutoff circuit 6 control the contactor not only from the safety controller 26 but also by the switching signals 57 and 58 from the controller 25 to energize the inverter 5 and energize the brake 3. Can be blocked. Therefore, at normal times, every time the vehicle reaches the designated floor, the controller 25 controls the brake drive circuit 4 and the power cut-off circuit 6 with the switching signals 57 and 58 to cut off the power supply to the inverter 5 and the brake 3 and The car 1 is stopped. Further, the arithmetic devices 32 and 37 of the safety controller 26 take in the state signals 53 to 56 indicating the states of the power cut-off circuit 6 and the brake drive circuit 4, and thereby detect the stop of the car 1.

  As in the previous embodiment, the arithmetic devices 32 and 37 have the same configuration, and the arithmetic device 32 will be described here. The arithmetic unit 32 includes a correction unit 60 as shown in FIG. 6 in addition to the configuration having the arithmetic unit 43, the input unit 44, the output unit 45, and the comparison unit 46 as described in FIG. The correction unit 60 receives a state signal 53 and a state signal 54 indicating the states of the energization cutoff circuit 6 and the brake drive circuit 4, and also receives an acceleration sensor signal 31 from the acceleration sensor 24, and a corrected signal after processing. 61 is given to the calculation unit 43. Specific processing in the correction unit 60 will be described with reference to FIG.

  In FIG. 7, the difference from FIG. 4 described above will be described. The correction unit 60 includes a car stop determination unit 62 and an offset measurement unit 63. The former car stop determination unit 62 takes in the state signals 53 and 54 indicating the current states of the energization cutoff circuit 6 and the brake drive circuit 4 and determines whether or not the car 1 is stopped. When the car stop determination unit 62 determines that the car 1 is stopped, the car speed calculation unit 52 is given the reset signal 64 as the correction signal 61 shown in FIG. Reset the car speed V2 to zero.

  Further, when the car stop determination unit 62 determines that the car 1 is stopped, the latter offset measurement unit 63 uses the acceleration sensor signal 31 of the acceleration sensor 24 to set an offset value α0, that is, 1G (gravity acceleration). ) And the offset signal 65 as the correction signal 61 shown in FIG. Here, the car stop determination unit 62 determines whether the car 1 is stopped based on the state signals 53 and 54 indicating the states of the energization cutoff circuit 6 and the brake drive circuit 4. The same applies to a configuration in which a signal indicating that the car 1 is stopped is received.

  When the car speed calculator 52 receives the reset signal 64, the car speed calculator 52 gives priority to the reset signal 64 and resets the car speed V2 obtained by the car speed calculator 52 to zero. Is calculated by calculating the corrected car speed V2. After that, as in the previous embodiment, the comparison unit 46 compares the car speed V1 obtained by the car position speed computation unit 51 with the car speed V2 obtained by the car speed computation unit 52, and the difference between the two is compared. Is determined to be within a predetermined range. As a result of the determination, if the difference between the two is within a predetermined range, it is determined that the encoder 21 and the acceleration sensor 24 are functioning normally. If the difference between the two is not within the predetermined range, the encoder 21 Alternatively, it is determined that one of the acceleration sensors 24 has failed, and an abnormality determination signal, for example, a signal for stopping the car 1 or a signal for notifying occurrence of an abnormality is output.

  According to the elevator according to this embodiment, by using the car speed V1 obtained from the encoder 21 and the car speed V2 obtained from the acceleration sensor 24, a common cause failure that is a concern when the same type of sensors are simply duplicated is used. The possibility can be eliminated, and the reliability of the encoder failure diagnosis can be further improved. In addition, when the car 1 stops, the car speed V2 obtained by the car speed calculation unit 52 is reset to zero using the acceleration sensor signal 31 acquired from the acceleration sensor 24. Therefore, both the encoder 21 and the acceleration sensor 24 are used. Even if it is normal, it is possible to prevent accumulation of errors due to long-time integration calculation, and to prevent the car speed V2 obtained from the acceleration sensor signal 31 from deviating from the car speed V1 obtained from the encoder signal 28. be able to.

  When the car stop determination unit 62 determines that the car 1 is stopped, the offset value α0 is measured using the acceleration sensor signal 31 of the acceleration sensor 24, and the car speed calculation unit 52 determines the acceleration sensor signal 31. Since the car speed V2 corrected by subtracting the offset value α0 is calculated from the car speed V1, the car speed V1 obtained from the encoder 21 while correcting the occurrence of an error difference even if the acceleration sensor 24 is used, and the acceleration sensor 24 The obtained car speed V2 can be compared with higher accuracy.

  FIG. 8 shows a flowchart in the case where a failure diagnosis process for diagnosing whether or not the dual encoder 21 has failed by a program installed in the control devices 32 and 37 is shown. This program is executed periodically using the timers of the control devices 32 and 37.

  First, in step S1, it is determined whether or not the car 1 is stopped. If the vehicle is stopped, the car speed V2 is reset to zero in step S2, and the offset value α0 of the acceleration sensor 24 is measured in step S3. In step S4, the car speed V1 is calculated from the encoder signal 28. In step S5, the offset value α0 is subtracted from the acceleration sensor signal 31, and the car speed V2 is obtained by integral calculation. In step S6, it is determined whether or not the difference between the car speeds V1 and V2 is greater than or equal to a predetermined value. If the difference is greater than or equal to the predetermined value, it is determined that the encoder 21 has failed, and a car stop signal is output in step S7. However, if it is determined in step S1 that the car 1 is not stopped, the correction process is not performed and the process proceeds to step S4 with the offset value α0 = 0.

  Further, in another embodiment of the present invention, as shown in FIG. 9, in addition to the correction process at the time t1 when the car 1 is stopped, the correction process can be performed when the car 1 is operating. Such correction processing during the operation of the car 1 is performed by third speed detection means provided on the main rope 10 side, for example, the motor 2 side, in addition to other speed detection means such as the acceleration sensor 24 and the encoder 21. A certain other encoder is provided, the signal from the third speed detecting means is also taken at times t2 and t4, and the car speed V3 obtained from the third speed detecting means by the correcting unit 60 is used to obtain from the acceleration sensor 24. The car speed V2 can also be corrected so as to approximate the car speed V3.

  However, if another encoder is provided on the main rope 10 side as the third speed detecting means, generally, a slip 66 may occur in the main rope 10, and there is a risk of detecting this as a difference occurrence to be corrected. is there. Therefore, when the rapid speed change of the car speed V3 obtained from the main rope side encoder value as the third speed detecting means is monitored and this rapid speed change is detected at the time point t3, it is determined that the slip occurs 66. However, it is possible to take measures such as not performing correction during the slip occurrence period.

  According to such an elevator, when the failure diagnosis of the encoder 21 that constitutes one of the duplex systems is performed using another type of acceleration sensor 24 that constitutes the other of the duplex systems, the same type of sensors can be used. It is possible to eliminate the possibility of common cause failure that is a concern, improve the reliability of encoder failure diagnosis, and provide a safer elevator. In addition, when the acceleration sensor 24 is used, an integration error accumulates when the car speed is calculated, and the deviation from the car speed V1 obtained from the detected value from the encoder 21 may increase, but the elevator operates for a long time. By taking advantage of the fact that it does not continue, resetting the car speed V2 calculated each time the elevator stops to zero, or performing corrections using values of other encoders provided on the main rope 10 side during operation Therefore, accumulation of integration errors can be prevented, and encoder fault diagnosis can be performed correctly.

  In each of the above-described embodiments, the failure diagnosis process of the encoder 21 provided in the governor 13 or the failure diagnosis process of either one by comparing the car speeds V1 and V2 calculated using the encoder 21 and the acceleration sensor 24. However, instead of the encoder 21 provided in the governor 13, other car speed detecting means, for example, a roller-type car speed sensor provided in the car 1 can be used. Further, in each of the above-described embodiments, the elevator having the duplicated arithmetic devices 32 and 37 has been described. However, the present invention is applied to either the configuration controlled by one arithmetic device or the duplicated arithmetic devices 32 and 37. Can be applied.

DESCRIPTION OF SYMBOLS 1 Passenger car 2 Motor 3 Brake 4 Brake drive circuit 5 Inverter 6 Energization cut-off circuit 7 AC power supply 10 Main rope 11 Counterweight 12 Governor rope 13 Governor 14 Gripping device 15 Emergency stop device 16 Rail 17 Buffer 21 Encoder 22 Final limit switch 23 Final limit Switch 24 Acceleration sensor 25 Control controller 26 Safety controller 27 Inverter control signal 28 Encoder signal 29 Switch signal 30 Switch signal 31 Acceleration sensor signal 32 Computing device 33 Stop request signal 34 Switching signal 35 Switching signal 36 Emergency stop operation signal 37 Computing device 38 Stop Request signal 39 Switching signal 40 Switching signal 41 Emergency stop operation signal 42 AND circuit 43 Calculation unit 44 Input unit 45 Output unit 46 Comparison unit 47 Safety chain abnormality determination section 48 Terminal floor overspeed abnormality determination section 49 First speed limit 50 Second speed limit 51 Car position speed calculation section 52 Car speed calculation section

Claims (7)

In an elevator that has an arithmetic device that inputs signals from a plurality of sensors that detect the operating state of the car and determines an abnormality, and controls the car by an abnormality determination signal from the arithmetic device,
An acceleration sensor is provided in the car, and an arithmetic unit for calculating a car speed by inputting signals from the acceleration sensor and other speed detection means different from the acceleration sensor to the arithmetic unit, and the arithmetic unit An elevator comprising: a comparison unit that outputs the abnormality determination signal based on a result of comparing the two car speeds calculated in step (1).   The arithmetic unit outputs the abnormality determination signal that stops the car when a difference between the two car speeds is larger than a predetermined value as a result of comparison between the two car speeds in the comparing unit. The elevator according to claim 1.   2. The elevator according to claim 1, wherein the arithmetic unit is provided with a correction unit that resets a car speed calculated based on a value of the acceleration sensor to zero every time the car is stopped.   A car speed calculation unit that provides an offset measurement unit that measures the offset value of the acceleration sensor every time the car stops, and that uses the offset value of the offset measurement unit to calculate the car speed by the acceleration sensor. The elevator according to claim 1, wherein the elevator is provided.   The elevator according to claim 1, wherein the other speed detection means is an encoder.   Third speed detection means different from the one that has calculated the two car speeds is provided, and the calculation unit calculates the car speed calculated based on a signal from the acceleration sensor during the operation of the car. The elevator according to claim 1, further comprising a car speed calculation unit that corrects the car using a car speed calculated based on a signal from the speed detection means.   2. The elevator according to claim 1, further comprising a communication line that converts an output signal of the acceleration sensor provided in the car into a digital value and transmits the converted digital signal to the arithmetic device.

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