Description
ELEVATOR SAFETY SYSTEM
TECHNICAL FIELD [0001]
The present invention relates to an elevator safety system, in particular, an elevator safety system suitable for detecting the vertical position of a cage.
BACKGROUND ART [0002]
In the case of elevators according to the related art, the vertical position of a cage that is travelling is detected indirectly by counting the output pulses from a pulse generator connected to an electric motor that drives the cage. For this position of the cage during travel, a remaining travel distance, which is a difference with respect to a floor height table (absolute position) for a floor at which the cage is to stop, is determined, and the position is used for generating a speed command according to the remaining travel distance. A shielding plate is installed near the stop position at each floor, and a position detector is mounted on the cage side so as to be opposed to this shielding plate. Upon starting the elevator system, an operation of measuring the absolute position of each floor in order from the lowest position is performed. [0003]
For example, as this type of elevator, there is one in
which, with an object to be detected on each floor side and a detector on the cage side forming a one-to-one pair, the presence of the cage at a landing position is detected when they are opposed to each other (see Patent Document 1). In addition, there is also one in which a sensor for directly detecting a sill, a toe guard, a fascia plate or the like as an attachment at each floor is mounted on the cage side, so that cage position correction information for the cage as it passes each floor is obtained without providing a special object to be detected at each floor (see Patent Document 2). Further, there is one that proposes a reduction in the time reguired for recovery in the event of an abnormality such as power outage, by providing a bar code that differs for each floor on the building side at each floor, and a sensor on the cage side, and by detecting the floor number of the closest floor (see Patent Document 3). Furthermore, there is one in which a plurality of objects to be detected made of magnets or the like for coding information unique to each floor are provided near the hall at each floor, and a number of detectors greater than that of the objects and capable of being opposed to the objects are installed on the cage side, thereby making it possible to obtain information such as floor data and door opening zone (see Patent Document 4). [0004]
Also, there is proposed a method in which a plurality of reflection-type photo-detectors are provided on the cage side, a single large object to be detected that is opposed to all the photo-detectors is installed on the floor side, and changes in cage position from just short of a landing position to the
landing are detected discretely on the basis of the individual detectors being sequentially switched from OFF to ON in accordance with the cage position (see Patent Document 5). Further, there is one in which a plurality of detectors are provided on the cage side, and an object to be detected is provided on the floor side, and when a landing error exceeds a predetermined value, an alarm illumination is automatically provided depending on the condition of whether the cage is located just short of or past the landing position (see Patent Document 6). Furthermore, there is one in which a coded object to be detected and a plurality of detectors are respectively provided on the hoistway side and on the cage side to thereby detect a floor at which the cage is present (see Patent Document 7) .
Patent Document 1: JP-A No. S60-223770 Patent Document 2: JP Patent No. 3744271 Patent Document 3: JP-A No. H7-157220 Patent Document 4: JP-A No. H7-257845 Patent Document 5: JP-A No. 2000-143109 Patent Document 6: JP-A No. 2004-149273 Patent Document 7: JP-A No. 2006-256795
DISCLOSURE OF THE INVENTION
PROBLEM TO BE SOLVED BY THE INVENTION
[0005]
However, in the case of Patent Document 1 described above, it is impossible to determine deviation information or the like for times other than when the cage is accurately opposed to a
target floor. Also, in the case of Patent Document 2, it is impossible to determine the position of the cage when located just short of the landing position, its position at landing, or the like. Further, in the case of Patent Document 3 and Patent Document 7, only a rough floor number at which the cage is present can be found but the landing error or the like cannot be found, and it is required to code each floor information for each individual floor. Furthermore, in the case of Patent Document 4 as well, it is required to code each floor information. In addition, while Patent Document 5 states that it is possible to detect process changes up to just short of the landing, there is no specific mention about the method of use, nor is there any mention about detection of an error detection amount at the time when the cage comes to a stop after going past a floor. Further, in the case of Patent Document 6, while it is possible to determine the level of landing deviation, only two levels, normal and abnormal, can be detected. [0006]
The present invention has been made in view of the circumstances surrounding the related art, and it is an object of the present invention to provide an elevator safety system which makes it possible to detect the vertical position of the cage with high reliability and ease, and which, in particular, makes it possible to detect a landing error between the cage floor and the landing floor mentioned above in multiple levels.
MEANS FOR SOLVING THE PROBLEM [0007]
To attain the above-mentioned object, the invention according to Claim 1 of the present invention relates to an elevator safety system which has a cage that travels across and between a plurality of floors within a hoistway formed in a building, a driving device that drives the cage, and a controller that controls the driving device, and in which a vertical position of the cage is detected and reflected on elevator control, characterized in that the elevator safety system includes a plurality of objects to be detected placed on the same vertical line within the hoistway, and a plurality of detectors provided to the cage and each capable of being opposed to each of the objects in a pair, and a vertical position of the cage is detected on the basis of a plurality of output signals outputted from the detectors. [0008]
In the invention according to Claim 1 of the present invention configured as described above, a plurality of objects to be detected are placed on the same vertical line within the hoistway, a plurality of detectors each capable of being opposed to each object in a pair are provided to the cage, and the vertical position of the cage is detected on the basis of outputting or cutting-off of output signals following opposition and non-opposition between each object and each detector as the cage ascends and descends. In this way, by placing a plurality of objects to be detected on the hoistway side, providing a plurality of detectors, which are each paired with each object, on the cage side, and determining the vertical position of the cage on the basis of a plurality of output signals outputted from
the individual detectors, the cage position can be detected with high reliability and ease. [0009]
Also, the invention according to Claim 2 of the present invention is characterized in that a landing error between the cage floor and the landing floor is detected in multiple levels on the basis of output signals outputted from the detectors. [0010]
In the invention according to Claim 2 of the present invention configured as described above, a plurality of objects to be detected are placed on the hoistway side, a plurality of detectors each paired with each of the objects are provided on the cage side, and a landing error between the cage floor and the landing floor is determined in multiple levels on the basis of a plurality of output signals outputted from the individual detectors. [0011]
Further, the invention according to Claim 3 of the present invention is characterized in that the object and the detector in a pair are disposed so as to be opposed to each other with an offset to enable detection of a landing error between the cage floor and the landing floor, and a direction of landing deviation. [0012]
In the invention according to Claim 3 of the present invention configured as described above, the object and the detector in a pair are disposed so as to be opposed to each other with an offset, thereby enabling detection of a landing error between the cage floor and the landing floor, and the direction
of landing deviation. [0013]
Furthermore, the invention according to Claim 4 of the present invention is characterized in that second cage position detecting means for equivalently detecting a vertical position of the cage is provided, and a validity of detection by the detector facing the object is determined on the basis of cage position information from the second cage position detecting means. [0014]
In the invention according to Claim 4 of the present invention configured as described above, the validity of detection by the detector facing the object is determined on the basis of cage position information from the second cage position detecting means, thereby making it possible to enhance the reliability of detection of the vertical position of the cage. [0015]
Also, the invention according to Claim 5 of the present invention is characterized in that an elapsed time or a travelled distance from detection of opposition of the object by the detector to detection of opposition of the next object is measured, and a validity of detection by the detector facing the object is determined on the basis of the measured information. [0016]
In the invention according to Claim 5 of the present invention configured as described above, the elapsed time or the travelled distance from detection of opposition of the object by the detector to detection of opposition of the next object is measured, and the validity of detection by the detector facing
the object is determined by comparing this measured value with a reference value. Therefore, it is possible to enhance the reliability of detection of the vertical position of the cage. [0017]
Further, the invention according to Claim 6 of the present invention is characterized in that the object is provided to at least one of a sill, a toe guard, and a fascia plate at the floor. [0018]
In the invention according to Claim 6 of the present invention configured as described above, the object is provided to at least one of the existing sill, toe guard, and fascia plate provided to an elevator, thereby making it possible to simplify mounting of eguipment. [0019]
Furthermore, the invention according to Claim 7 of the present invention is characterized in that the object is a hole formed in at least one of a toe guard and a fascia plate. [0020]
In the invention according to Claim 7 of the present invention configured as described above, since the object is a hole formed in at least one of a toe guard and a fascia plate, it is possible to prevent the object from coming into contact with swinging objects within the shaft such as travelling cables in the event of an earthquake or high winds. [0021]
Also, the invention according to Claim 8 of the present invention is characterized in that arrival of the cage at a predetermined position just short of a target floor is detected
when the object on an upper side and the detector on a lower side are opposed to each other at the time of descend operation of the cage, and when the object on a lower side and the detector on an upper side are opposed to each other at the time of ascend operation of the cage. [0022]
In the invention according to Claim 8 of the present invention configured as described above, arrival of the cage at a predetermined position just short of a target floor can be reliably detected during each of descend operation of the cage and ascend operation of the cage, and this detection can be reflected on elevator control.
EFFECTS OF THE INVENTION [0023]
According to the present invention, the vertical position of the cage can be detected with reliability by means of a relatively simple structure in which detectors are provided on the cage side, and objects to be detected that can be opposed to the detectors are disposed on the hoistway side. In particular, various kinds of cage position detection, including the grasping of a landing error at the time when the cage stops at each floor, can be performed by common equipment, thereby achieving a reduction in facility cost. In addition, since the detected cage position information undergoes multiple stages of careful examination, a further enhancement in system reliability can be achieved. Further, the landing error of the cage with respect to a target floor to stop at can be detected in multiple levels,
thereby making it possible to achieve determination of whether the current condition is such that a serious abnormality that requires immediate maintenance is occurring or continuation of operation is possible to some extent, issuing of an appropriate alarm to the passengers, and accurate grasping of the elevator condition from an external location.
BEST MODE FOR CARRYING OUT THE INVENTION
[0024]
Hereinbelow, an embodiment of an elevator safety system according to the present invention will be described with reference to the drawings.
[0025]
Fig. 1 is an overall configuration diagram showing a first embodiment of an elevator safety system according to the present invention, Fig. 2 is a schematic diagram showing an opposed relation between detectors and objects to be detected according to the first embodiment, Fig. 3 is an explanatory diagram showing opposed relations between the detectors and the objects, and output states of signals according to the first embodiment, Fig. 4 is a schematic diagram showing an opposed relation between the detectors and other objects to be detected according to the first embodiment, Fig. 5 is a flowchart showing the procedure of a system boot-up process. Fig. 6 is a flowchart showing the procedure of a floor-height-table creating process, Fig. 7 is a flowchart showing the procedure of an opposition-detection diagnosis process, Fig. 8 is a flowchart showing the procedure of another opposition-detection diagnosis process, Fig. 9 is a
flowchart showing the procedure of an opposition-detection-kind determining process, and Fig. 10 is a flowchart showing the procedure of a deceleration-speed-command generating process. [0026]
As shown in Fig. 1, in an elevator, a cage 1 that travels across and between a plurality of floors within a hoistway formed in a building is connected to a counterweight 3 via a rope 2, and is suspended from a sheave 4 and a deflector sheave 5. The sheave 4 is driven by a drive motor 6, and driving power is supplied from a power converter 7 to the drive motor 6. A pulse generator 8 is mounted to the drive motor 6. As pulses generated with the rotation of the drive motor 6 are counted by a system controller 9, the speed of the drive motor 6, the eguivalent vertical position of the cage 1, and the travelled distance of the cage 1 are calculated. Further, the cage 1 is provided with a cage-side door 11 that opens and closes through engagement with a hall-side door 10. When the positioning error between the floor surface at each floor and the cage floor surface is within a predetermined range when the elevator stops, the two doors 10 and 11 are permitted to engage with each other so as to open. It should be noted that the second cage position detecting means for equivalently detecting the vertical position of the cage 1 described above includes, for example, the pulse generator 8 and the system controller 9. [0027]
As the elevator safety system according to the first embodiment, a plurality of detectors 13, 14 are mounted on the cage 1 side via a bracket 12, and within the hoistway, a
plurality of objects to be detected 17, 18 respectively capable of being opposed to the detectors 13, 14 in pairs are placed on the same vertical line. For example, in the case of the N-th floor, the objects 17, 18 are mounted to a sill 15 on the floor via a bracket 16. Here, the object 13 and the detector 17 in a pair, and the object 14 and the detector 18 in a pair are installed so as to be offset from each other. That is, as shown in Fig. 2, the vertical center-to-center distance Dp between the objects 17, 18 is set narrower than the vertical center-to-center distance Ds between the detectors 13, 14. This is to exert an effect such that three or more conditions are identified on the basis of a direct opposition degree indicating the degree of opposition between the objects 17, 18 and the detectors 13, 14, and the condition of opposition is used for system control. [0028]
For example, the following conditions are detected: (A) The state of opposition is such that the direct opposition degree is high (for example, the absolute value of the landing error between the floor surface at the N-th floor and the cage floor surface is small), the detectors 13, 14 have each detected an object to be detected, and the output states of both the detectors indicate that an object to be detected is "Present"; (B) The direct opposition degree is slightly low and the cage floor surface is located above the floor surface at each floor, and the output states of the detector 13 and detector 14 indicate that an object to be detected is "Not Present" and an object to be detected is "Present", respectively; (C) The direct opposition degree is slightly low and the cage floor surface is located
below the floor surface at each floor, and the output states of the detector 13 and detector 14 indicate that an object to be detected is "Present" and an object to be detected is "Not Present", respectively; and (D) The state of opposition is such that the direct opposition degree is very low (for example, the absolute value of the landing error between the floor surface at each floor and the cage floor surface is large), and the output states of both the detectors 13, 14 indicate that an object to be detected is "Not Present" . Output signals from the respective detectors 13, 14 are transmitted as detection signals to a position detection processor 22 via respective interfaces 20, 21. Then, in response to the two sets of "Present" and "Not Present" detection signals, the position detection processor 22 transmits, to the system controller 9, logical outputs of landing error such as "normal landing", "slightly faulty: upward deviation: there is a landing error in which the cage floor surface is located above the floor surface", "slightly faulty: downward deviation: there is a landing error in which the cage floor surface is located below the floor surface", and "abnormal landing". The system controller 9 reflects these logical outputs on, for example, a position correcting process on the cage 1, a service process for alarming the elevator user in the form of a voice guidance, or a process of sending the outputs to a maintenance company in the form of abnormality precursor information or emergency maintenance reguest information. [0029]
The output signals outputted from the detectors 13, 14 are used not only for the determination of a landing error when the
cage 1 comes to a stop, but also for other applications, for example, creation of a speed command, and detection of the door zone. That is, supposing an ascend operation, for example, while the cage 1 comes to a stop in a state in which the object 17 and the detector 13, and the object 18 and the detector 14 are opposed to each other upon landing of the cage 1, just short of the time when this landing state is reached ( ~ Dp/2 + a, where a is a numerical value determined by the object width, detector width, and sensitivity), the object 18 and the detector 13 come into opposition to each other once. The output signal outputted at this time represents information indicating that the cage 1 has reached a predetermined position just short of a target floor, and this information can be reflected on creation of a speed command. In addition, depending on the setting of the distance between the objects 17, 18 (equivalently, the center-to-center distance Dp), this information can be also reflected on detection of the door zone. [0030]
Further, in the first embodiment, there are provided not only the objects 17, 18 that are opposed to the detectors 13, 14 when the cage 1 stops at the N-th floor, but also, for example, objects to be detected 23, 24 that are mounted to a fascia plate 26 between the N-th floor and the (N-l)-th floor so as to be capable of being opposed to the detectors 13, 14, and used together for detecting when a predetermined position has been passed within the hoistway. The objects 23, 24 are provided for, for example, detecting when the cage 1 has passed a predetermined deceleration position at an end portion (upper end portion in
this example), in order to prevent the cage 1 from colliding against the top portion in the event of an abnormality. Unlike in the case of multiple-level detection of the objects provided at each floor to find a landing error, as the state of opposition to be detected at this time, it suffices to detect only a perfect opposition. Thus, as shown in Fig. 4, the center-to-center distance Dp 1 between the object 23 and the object 24 is set equal to the vertical center-to-center distance Ds between the detectors 13, 14. At this time, if detection of passage of a predetermined deceleration position is recognized on the basis of the logical product of the opposition between the object 23 and the detector 13 and the opposition between the object 24 and the detector 14, a dual detection system is provided for enhanced reliability. [0031]
In addition, for example, the accuracy of validity determination on the detection of opposition between an object to be detected and a detector increases by using, for a reasonableness check on the cage position detection system, composite information such as the fact that during ascend operation, the object 24 and the detector 13 come into opposition to each other, then the object 23 and the detector 13, then the object 24 and the detector 14, and then the object 23 and the detector 14 come into opposition to each other sequentially, the fact that these oppositions take place such that these events occur with a time difference that takes the travelling speed into consideration, and the detection interval of other plurality of sets of objects to be detected. Further, it is possible to
provide enhanced reliability by transmitting this logical signal to the system controller 9, and by matching it with a predetermined position passage timing of the cargo position information which is calculated by counting pulses of the pulse generator 8 attached to the drive motor 6 and a pulse generator
(not shown) driven by a governor rope for connecting the cage 1 and a speed governor (not shown)to each other.
[0032]
If the two objects 23, 24 installed intermediate between a floor and a floor, and the two objects 17, 18 installed at each floor are shaped as an integral structure in such a way that the objects 23, 24 have a dimension allowing them to come into opposition to the two detectors 13, 14 in order to perform passage detection, and that the objects 17, 18 have such a dimension that their center-to-center distance is slightly shorter than the center-to-center distance between the two detectors 13, 14 in order to generate multi-level outputs, and the integral structure is mounted to equipment within the shaft via a bracket 25 or the like, dimension adjustment and mounting can be facilitated.
[0033]
Here, a detailed description will be given of the configuration of the detectors 13, 14 and the objects 17, 18 with reference to Figs. 2 and 3. The center-to-center distance Ds between the detector 13 and the detector 14 is shorter than the center-to-center distance Dp between the objects 17, 18 and, as shown in the same drawings, the detector 13 and the object 17, and the detector 14 and the detector 18 are set so as to be
opposed to each other with appropriate overlaps (both the detector 13, 14 detect the objects 17, 18, and their outputs become ON) . Accordingly, when the cage 1 comes to a stop with slight upward/downward deviation, one of the detectors 13, 14 is not opposed to an object to be detected, which produces an effect such that it is possible to detect in which one of upward and downward directions a landing abnormality has occurred. Here, the detectors 13, 14 are each constructed from, for example, an eddy current sensor, and the objects 17, 18 are each constructed from, for example, a metal strip, and a gap of several tens of millimeters can be set in a direction perpendicular to the plane of the drawings, thereby making it possible to avoid their contact due to lateral shaking during travel. [0034]
It should be noted here that if the two objects 17, 18 are molded integrally with the bracket 16, the mounting operation can be facilitated. In addition, by also integrally molding the detectors 13, 14 with a non-ferrous fitting of non-magnetic metal or resin that is not readily detected by an eddy current sensor, their mounting to the cage 1 can be facilitated. Fig. 3 shows the relationship between positional relations between the detectors 13, 14 and the objects 17, 18, and the outputs 013, 014 of the detectors 13, 14. The state (1) is a state in which the outputs 013, 014 are both OFF and the cage 1 has stopped at a position largely deviating from the normal landing position, indicating an occurrence of some system abnormality that requires immediate maintenance. It should be noted here that if the detecting body 17 is set so as to be elongated slightly more in the upward
direction, this also allows for application to detection of the door zone. The state (2) is a state in which the output 013 is ON and the output 014 is OFF, and the landing position slightly deviates upwards, although not to an abnormal level. Although there is no need for emergency maintenance, this state can be used for remote alarm-level monitoring. The state (3) represents a normal landing state, in which both the objects 17, 18 and the detectors 13, 14 are opposed to each other, and the outputs 013, 014 of the two detectors 13, 14 both become ON. Normally, this state is entered upon stoppage at each floor. The state (4) is a state in which 013 is OFF and the output 014 is ON, and the landing position slightly deviates downwards, although not to an abnormal level. Although there is no need for emergency maintenance, this state can be used for remote alarm-level monitoring. The state (5) represents an abnormal landing state like the state (1), and this state can be grasped from the OFF states of the two outputs 013, 014.
[0035]
Although it is impossible to discriminate between the state
(5) and the state (1) since the output is off from this information on the outputs 013, 014 alone, such discrimination can be made by also using operation sequence information. For example, assuming a descend operation, pulse signals from the pulse generator 8 are counted by the system controller 9 to perform rough calculation of the cage position. If the cage 1 comes to a stop without the objects 17, 18 and the detectors 13, 14 coming into opposition to each other near a landing floor, this state can be identified as the state (1), and if the cage 1
comes to a stop near a landing floor after going through the states (2) , (3), and (4), this state can be determined as the state (5) . In this way, if information from the second cage position detecting means other than the objects 17, 18 and the detectors 13, 14, that is, the pulse generator 8 and the system controller 9 is used in combination, the landing state of the cage 1 can be grasped with high reliability in two or more states when stopping at each floor. [0036]
Here, with reference to Fig. 4, a detailed description will be given of the configuration of the objects 23, 24, and the relationship between the objects 23, 24 and the detectors 13, 14. As shown in Fig. 1, the objects 23, 24 are position detecting devices for the cage 1 which are installed between a floor and a floor and used for effecting emergency deceleration at a terminal floor. Unlike in the case of the objects 17, 18 that are objects to be detected installed at each floor, for the objects 23, 24, there is no need to check a landing error. Thus, as shown in Fig. 4, the center-to-center distance Dp 1 between the objects 23, 24 is set to the same value as the center-to-center distance Ds between the detectors 13, 14. It should be noted that the outputs 013, 014 of the detectors 13, 14 eventually become the same output signal with the elapse of time. Thus, if both the signals are taken into an independent processor and compared against each other, this produces an another effect in that the reliability of the cage position detection system is enhanced. In addition, since the progression over time of output signals in the case when the detectors 13, 14 come into opposition to the objects 23,
24 installed at an intermediate floor differs from that of detector output signals in the case when the objects installed at each floor are passed without stopping, there is also another effect in that the soundness of the detectors 13, 14 can be also checked by a logical check between a plurality of objects to be detected. [0037]
Next, the procedure of a system boot-up process Ml will be described with reference to Fig. 5. When the power of the system controller 9 is turned on, or a system reset is performed, the boot-up process Ml is executed. In M100, a system-initial-value setting process M100 such as clearing of the RAM or initialization of I/O is executed, and an interrupt wait state M101 is entered. Although not shown, examples of interrupt include a timer interrupt that generates an interrupt at a fixed time interval by counting a clock with a counter, and an opposition-detection interrupt which is generated by the position detection processor 22 at the time when the objects 17, 18 are detected by the detectors 13, 14 opposed thereto. [0038]
Next, the procedure of a floor-height-table creating process M2 will be described with reference to Fig. 6. In this process, the positions of a plurality of objects to be detected installed at individual floors are measured in order from the lowest portion, thereby creating a table of positions of the objects. First, upon activation of this process, in process M201, it is determined whether or not an execution command for a floor height measuring operation has been issued. If this is NO, then
the process returns to an interrupt wait via return process M202. If the execution command has been issued, first, low-speed operation is performed until reaching the lowest floor in process M203 to prepare for measurement. Then, in process M204, after reaching the lowest floor, the position counter from the lowest portion to be created as a table of installed positions of objects to be detected is reset, and an ascend operation is started at low speed while measuring the traveled distance. In process M205, it is determined whether or not the highest portion as a measurement end point has been reached, and if this has not been reached, in process M206, the measuring operation is continued, and in accordance with an interrupt generated when an object to be detected and a detector come into opposition to each other, a process of writing the travelled distance from the lowest portion at that time to the table is continued. Upon reaching the highest floor, the process returns to an interrupt wait via process M202, and the measuring operation is ended, making it ready to shift to the normal operation. [0039]
Here, with reference to Fig. 7, a description will be given of the procedure of an opposition-detection diagnosis (A) process M3 activated by a detecting-object interrupt. This is a reliability enhancement process in which, with regard to the validity of detection of the opposition between the objects 17, 18 and the detectors 13, 14, detection of an opposition that has occurred in an area where detection of an opposition is highly likely to occur is determined as valid, from position information obtained from the second cage position detecting means, such as
the pulse generator 8 mounted to the drive motor 6 of the cage 3 or a pulse generator rotated by an unillustrated governor driving rope, and the floor height table. First, in process M301, the position of the cage 1 is detected by the second cage position detecting means, and then in process M302, the floor height table is searched to determine whether or not an object to be detected is present in close proximity to this cage position. If this is YES, in process M303, the opposition detection is determined as normal, and various restrictions are not placed. If the object is not present in close proximity, in process M304, it is determined that an abnormality has occurred in the detection, and a process of making the detection itself invalid is performed, that is, a notification is given to a higher level controller to the effect that an abnormality has occurred in the object detection sequence, and the process returns to an interrupt wait via process M306. It is thus possible to enhance the reliability of detecting-object detection. It should be noted that while in this example it has been described for the sake of convenience that the validity of detection of the opposition between the objects 17, 18 and the detectors 13, 14 is determined, it is needless to mention that the validity of detection of the opposition between a plurality of objects to be detected installed at individual floors and the detectors 13, 14 is determined. [0040]
Next, with reference to Fig. 8, a description will be given of the procedure of an opposition-detection diagnosis (B) process M4 activated by a detecting-object interrupt. Here, the validity of detection of the opposition between the objects 17, 18 and the
detectors 13, 14 is determined from the distance between a plurality of objects to be detected. In process M401, the travelled distance from the last detection of opposition is calculated, and it is determined in process M402 whether or not the value matches a value in the table. If the values substantially match, then in process M403, it is regarded that the functioning is normal, and the process is continued. If the values do not match, in process 404, an emergency measure such as not adopting a position detection interrupt is taken, and the check process is ended via process M405. While the method of using this determination result will be described later, on the basis of this, the reliability of detecting-object detection can be enhanced. While in this example the validity of detection of the opposition between an object to be detected and a detector is determined on the basis of the travelled distance from the last detection of opposition, this may be determined on the basis of the time elapsed from the last opposition detection. In addition, while in this example the validity of detection of the opposition between the objects 17, 18 and the detectors 13, 14 is determined, it is needless to mention that the validity of detection of the opposition between a plurality of objects to be detected installed at individual floors and the detectors 13, 14 is determined. [0041]
Next, the procedure of an opposition-detection-kind determining process M5 will be described with reference to Fig. 9. The objects 17, 18 used for detecting a landing error at each floor are set such that, in order to enable detection of opposing
positions in multiple levels, the distance between the objects 17, 18 is different from the distance between the detectors 13, 14. On the other hand, in the case of the objects 23, 24 used for effecting emergency deceleration at a terminal floor, it suffices to detect only the opposition, the objects 23, 24 are installed at positions directly opposing the detectors 13, 14. Therefore, it is necessary to discriminate between these detections. The opposition-detection-kind determining process M5 is a process of determining the kind of these objects. When a task is activated by an opposition-detection interrupt or a timer interrupt at a short interval, in process M501, it is determined whether or not two detectors have received an interrupt at substantially the same time. If this is YES, it is determined that the objects are the objects 23, 24 other than the objects installed at each floor for detecting a landing error, and this information is used in process M502 such as detection of passage of a predetermined portion that is not described. For example, the speed when an end portion is passed is checked, and if the speed is equal to or more than a predetermined value, a process of applying emergency deceleration, or a process of correcting the cage position information by this fixed-point passage information is performed. On the other hand, if an interrupt has been detected by one of the detectors 13, 14 at a time, it is determined that the objects 17, 18 for detecting a landing error have been detected, and this information is used in process M503. For example, by combination with the cage speed information, if the cage 1 is at a stop, this information is used for determining the level of a landing error as described above.
[0042]
Here, an application to a deceleration-speed-command generating process M6 will be described with reference to Fig. 10. A speed command generation is a timer task and activated every predetermined period of time. Upon activation, a deceleration speed command Vr is calculated in process M601 by computing the square root of the product of a predetermined deceleration and a remaining travel distance to a target floor to stop at. In process M602, if there is a remaining distance to the target floor to stop at, the speed command Vr is used by the speed control system as it is. If the cage 1 is approaching a position near the floor to stop at, the speed command Vr is switched. That is, from the timing when a point just short of the floor to stop at is passed, the speed command is switched to a speed command appropriate to the information on the distance just short of the floor to stop at. If the cage 1 is immediately before a stop, it is determined in process M604 whether or not there is an abnormality in the opposition detecting system by looking at the results of the diagnosis processes M3, M4, and if there is no abnormality, as a normal process in process M605, the speed command is switched to a speed command appropriate to the information on the distance just short of the floor to stop at, and the speed command generating process is ended. On the other hand, if there is an abnormality in the opposition detecting system, there is a possibility that the information on the distance just short of the floor to stop at is inaccurate. Accordingly, as an abnormal process, in process M606, instead of switching to a speed command appropriate to information on the
distance just short of a level, an emergency escape process is executed whereby it is continued to use the deceleration command Vr based on remaining distance information which, although subject to some degree of landing error, is a more reliable piece of information. If the determination result on the reasonableness of detection of opposition is reflected on a deceleration speed command in this way, there is an effect in that the system reliability is enhanced. [0043]
According to the first embodiment, the vertical position of the cage 1 can be detected with reliability by means of a relatively simple structure in which the detectors 13, 14 are provided on the cage 1 side, and the objects 17, 18, 23, 24 that can be opposed to the detectors 13, 14 are disposed on the hoistway side. In particular, various kinds of cage position detection, such as the grasping of a landing error at the time when the cage 1 stops at each floor, the grasping of abnormal approaching of the cage 1 to a terminal floor, and the grasping of arrival of the cage 1 at a predetermined position just short of a target floor, can be performed by common equipment, thereby achieving a reduction in facility cost. In addition, since the detected cage position information undergoes multiple stages of careful examination, a further enhancement in system reliability can be achieved. Further, the landing error of the cage 1 with respect to a target floor to stop at can be detected in multiple levels, thereby making it possible to achieve determination of whether the current condition is such that a serious abnormality that requires immediate maintenance is occurring or continuation
of operation is possible to some extent, issuing of an appropriate alarm to the passengers, and accurate grasping of the elevator condition from an external location. Furthermore, since the objects 17, 18, 23, 24 are mounted to the existing sill 15, toe guard 19, or fascia plate 26 already provided to the elevator, mounting of equipment can be simplified. In addition, by constructing each of the detectors 13, 14 and the objects 17, 18 from an eddy current sensor and a metal strip, respectively, it is possible to achieve accurate opposition detection even within a dusty hoistway.
[0044]
Fig. 11 is an enlarged main-portion diagram showing a second embodiment of the elevator safety system according to the present invention, Fig. 12 is a schematic diagram showing an opposed relation between detectors and objects to be detected according to the second embodiment of the present invention, and Fig. 13 is an explanatory diagram showing opposed relations between the detectors and the objects, and output states of signals according to the second embodiment of the present invention. It should be noted that portions equivalent to those described above are denoted by the same reference numerals, and features associated with other pieces of equipment will be described with reference to Fig. 1.
[0045]
As shown in Fig. 11, in the elevator safety system according to the second embodiment, holes are formed in the toe guard 19 as a plurality of objects to be detected 27, 28, which are placed on the same vertical line within the hoistway and can
be respectively opposed to the detectors 13, 14 on the cage 1 side in pairs. That is, the objects 27, 2 8 are detected by the detectors 13, 14 as negative logics of presence. For example, the detectors 13, 14 are constructed as eddy current sensors, and as for the objects 27, 28, the objects are equivalently constructed by forming small holes in the toe guard 19 constructed from a magnetic material, and when in opposition to the detectors 13, 14, "Not Present" (= negative logic of "Present") is detected, and when not in opposition to the detectors 13, 14, "Present" (= negative logic of "Not Present") is detected. [0046]
Here, with reference to Figs. 12 and 13, a description will be given of the configuration of the objects 27, 28, and relations between the objects 27, 28 and the detectors 13, 14. The center-to-center distance Ds between the detector 13 and the detector 14 is shorter than a center-to-center distance Dp 2 between the objects 27, 28 and, as shown in the same drawings, the detector 13 and the object 27, and the detector 14 and the object 28 are set so as to be opposed to each other with appropriate overlaps. Upon normal landing of the cage 1, as shown in Fig. 12, the outputs 013, 014 both become OFF. For detection of a floor, this signal can be used by being read as a negative logic. Fig. 13 shows the progression of the positional relation between the detectors 13, 14 and the objects 27, 28 over time from a state (1) of being in close proximity to a target floor to a normal landing state (5) . It can be appreciated that a plurality of landing states can be detected before the normal landing state (5) is reached.
[0047]
According to the second embodiment, by forming the objects 27, 28 as holes in the toe guard 19, the cage position can be detected without creating protrusions on the hoistway, thereby making it possible to prevent swinging objects within the shaft such as travelling cables from coming into contact with the objects 27, 28 in the event of an earthquake or high winds. [0048]
Fig. 14 is a schematic diagram showing a third embodiment of the elevator safety system according to the present invention, and Fig. 15 is an explanatory diagram showing opposed relations between detectors and objects to be detected, and output states of signals according to the third embodiment. It should be noted that portions equivalent to those described above are denoted by the same reference numerals, and features associated with other pieces of equipment will be described with reference to Fig. 1. [0049]
As shown in Fig. 14, in the elevator safety system according to the third embodiment, there are provided a plurality of objects to be detected 37, 38 that are placed on the same vertical line within the hoistway and can be respectively opposed to the detectors 13, 14 on the cage 1 side in pairs, and holes 37a, 38a are formed in the objects 37, 38. The center-to-center distance Ds between the detector 13 and the detector 14 is shorter than a center-to-center distance Dp 3 between the objects 37, 38 and, as shown in the same drawings, the detector 13 and the object 37, and the detector 14 and the object 38 are set so as to be opposed to each other with appropriate overlaps. While
the basic detecting action is substantially the same as that in the second embodiment described above, since the holes 37a, 38a are formed in the objects 37, 38, as shown in Fig. 15, detection of a landing error can be grasped in a greater number of levels. While the example in Fig. 15 illustrates a case in which, beginning with a normal landing state (1), the cage 1 comes to a stop with a landing error that becomes gradually greater with respect to the downward direction, for example, a landing error can be detected with the detectors 13, 14 and the objects 37, 38 in eight steps up to a state (9) in which an extremely large landing error has occurred.
BRIEF DESCRIPTION OF THE DRAWINGS [0050]
Fig. 1 is an overall configuration diagram showing a first embodiment of an elevator safety system according to the present invention.
Fig. 2 is a schematic diagram showing an opposed relation between detectors and obj ects to be detected according to the first embodiment.
Fig. 3 is an explanatory diagram showing opposed relations between the detectors and the objects to be detected, and output states of signals according to the first embodiment.
Fig. 4 is a schematic diagram showing an opposed relation between the detectors and other objects to be detected according to the first embodiment.
Fig. 5 is a flowchart showing the procedure of a system boot-up process.
Fig. 6 is a flowchart showing the procedure of a floor-height-table creating process.
Fig. 7 is a flowchart showing the procedure of an opposition-detection diagnosis process.
Fig. 8 is a flowchart showing the procedure of another opposition-detection diagnosis process.
Fig. 9 is a flowchart showing the procedure of an opposition-detection-kind determining process.
Fig. 10 is a flowchart showing the procedure of a deceleration-speed-command generating process.
Fig. 11 is an enlarged main-portion diagram showing a second embodiment of the elevator safety system according to the present invention.
Fig. 12 is a schematic diagram showing an opposed relation between detectors and objects to be detected according to the second embodiment of the present invention.
Fig. 13 is an explanatory diagram showing opposed relations between the detectors and the objects to be detected, and output states of signals according to the second embodiment of the present invention.
Fig. 14 is a schematic diagram showing a third embodiment of the elevator safety system according to the present invention.
Fig. 15 is an explanatory diagram showing opposed relations between detectors and objects to be detected, and output states of signals according to the third embodiment.
DESCRIPTION OF REFERENCE NUMERALS AND SYMBOLS [0051]
1 Cage
2 Rope
3 Counterweight
4 Sheave
5 Deflector sheave
6 Drive motor
7 Power converter
8 Pulse generator (second cage position detecting means)
9 System controller (second cage position detecting means)

10 Hall-side door
11 Cage-side door

12, 16, 25 Bracket
13, 14 Detector 15 Sill
17, 18, 23, 24, 27, 28, 37, 38 Objects to be detected
19 Toe guard
20, 21 Interface
22 Position detection processor
26 Fascia plate
Ds Distance between detectors
Dp, Dp 1, Dp 2 Distance between objects to be detected

CLAIMS
1. An elevator safety system which has a cage that travels
across and between a plurality of floors within a hoistway formed
in a building, a driving device that drives the cage, and a
controller that controls the driving device, and in which a
vertical position of the cage is detected and reflected on
elevator control, characterized in that
the elevator safety system comprises a plurality of objects to be detected placed on the same vertical line within the hoistway, and a plurality of detectors provided to the cage and each capable of being opposed to each of the objects in a pair, and a vertical position of the cage is detected on the basis of a plurality of output signals outputted from the detectors.
2. The elevator safety system according to Claim 1, characterized in that a landing error between the cage floor and the landing floor is detected in multiple levels on the basis of output signals outputted from the detectors.
3. The elevator safety system according to Claim 2, characterized in that the object and the detector in a pair are disposed so as to be opposed to each other with an offset to enable detection of a landing error between the cage floor and the landing floor, and a direction of landing deviation.
4. The elevator safety system according to Claim 1, characterized in that second cage position detecting means for
equivalently detecting a vertical position of the cage is provided, and a validity of detection by the detector facing the object is determined on the basis of cage position information from the second cage position detecting means.
5. The elevator safety system according to Claim 1, characterized in that an elapsed time or a travelled distance from detection of opposition of the object by the detector to detection of opposition of the next object is measured, and a validity of detection by the detector facing the object is determined on the basis of the measured information.
6. The elevator safety system according to Claim 1, characterized in that the object is provided to at least one of a sill, a toe guard, and a fascia plate at the floor.
7. The elevator safety system according to Claim 1, characterized in that the object is a hole formed in at least one of a toe guard and a fascia plate.
8. The elevator safety system according to Claim 1, characterized in that arrival of the cage at a predetermined position just short of a target floor is detected when the object on an upper side and the detector on a lower side are opposed to each other at the time of descend operation of the cage, and when the object on a lower side and the detector on an upper side are opposed to each other at the time of ascend operation of the cage.