EP1870368B1

EP1870368B1 - Elevator device

Info

Publication number: EP1870368B1
Application number: EP05730419.8A
Authority: EP
Inventors: Masanori c/o Mitsubishi Denki Kabushiki YASUE
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2005-04-13
Filing date: 2005-04-13
Publication date: 2019-04-03
Anticipated expiration: 2025-04-13
Also published as: EP1870368A4; EP1870368A1; WO2006112008A1; JPWO2006112008A1; CN101163636B; CN101163636A; JP4917030B2

Description

Technical Field

The present invention relates to an elevator apparatus equipped with an emergency stop device for forcibly stopping a car or a counterweight.

Background Art

In a conventional elevator apparatus, a car may be mounted with an emergency stop device which operates through an electromagnetic actuator to swiftly perform an operation of stopping the car. The electromagnetic actuator is operated by being supplied with a power from a battery (see Patent Document 1).
Patent Document 1: WO 2004-083091
As a further prior art document, JP 11 021 035 A refers to an elevator device provided with a power generating means for generating electric power by making use of the rotation of a roller guide for guiding a car of an elevator, a control means and an energy accumulating and supplying means.
JP 10 08 7212 A refers to a speed governor rope, which is suspended from the top part of a hoistway and laid in a vertical direction by fixed tension by a speed governor rope weight. The speed governor rope drives a sheave by a pulley in speed governor fixed to a car.
JP 6 183 660 refers to a device for preventing malfunction of a speed governor of an elevator, wherein a speed governor rope is wound on a pair of sheaves, which are supported by the upper-lower end parts of a hoistway and at least one of which has a speed governor in a loop form.

Disclosure of the Invention

Problems to be solved by the Invention

In recent years, small-sized, large-capacity batteries have been developed to be utilized for portable components and the like owing to the progress of battery technology. However, those batteries are not sufficient in terms of life or the like when they are used as a power source for an emergency stop device. Large-capacitance capacitors and the like have also been developed, but they are designed to use electric energy stored in the past and gradually discharge the electric energy as time elapses. Therefore, they are not guaranteed to supply power at a desired moment. Accordingly, there have been demands to cause an emergency stop device to operate more swiftly and more reliably.
The present invention has been made to solve the above-mentioned problems, and it is therefore an object of the present invention to obtain an elevator apparatus in which an emergency stop device for forcibly stopping raised/lowered bodies is allowed to operate more swiftly and more reliably when a car and a counterweight (raised/lowered bodies) are traveling at an excessively high speed.

Means for solving the Problems

An elevator apparatus according to the present invention includes the features of any of claims 1 or 2.

Brief description of the Drawings

Fig. 1 is a schematic diagram showing an elevator apparatus according to Embodiment 1 of the present invention.
Fig. 2 is a schematic diagram showing an essential part of the elevator apparatus of Fig. 1.
Fig. 3 is a lateral view showing the pulley device of Fig. 2.
Fig. 4 is a plan view showing an elevator apparatus according to Embodiment 2 of the present invention.
Fig. 5 is a front view showing an essential part of a pulley device of Fig. 4.

Best Modes for carrying out the Invention

Preferred embodiments of the present invention will be described hereinafter with reference to the drawings.

Embodiment 1

Fig. 1 is a schematic diagram showing an elevator apparatus according to Embodiment 1 of the present invention. Referring to the figure, a pair of car guide rails 2 and a pair of counterweight guide rails (not shown) are installed within a hoistway 1. A car 3 as a raised/lowered body is disposed between the respective car guide rails 2, and a counterweight 4 as a raised/lowered body is disposed between the respective counterweight guide rails. The car 3 is raised/lowered within the hoistway 1 while being guided by the respective car guide rails 2, and the counterweight 4 is raised/lowered within the hoistway 1 while being guided by the respective counterweight guide rails.
A deflector pulley 5, a hoisting machine 6 as a drive device for generating a driving force for raising/lowering the car 3 and the counterweight 4, are provided in an upper portion of the hoistway 1. The hoistingmachine 6 has a drive device body 7 including a motor, and a drive sheave 8 rotated by the drive device body 7. A plurality of main ropes 9 are looped around the deflector pulley 5 and the drive sheave 8. The car 3 and the counterweight 4 are suspended within the hoistway 1 by means of the respective main ropes 9. The car 3 and the counterweight 4 are raised/lowered within the hoistway 1 through rotation of the drive sheave 8.
The car 3 is mounted with a pair of emergency stop devices 10 facing the car guide rails 2, respectively. The emergency stop devices 10 have braking portions 11 for generating braking forces applied to the car 3 and electromagnetic drive portions 12 for operating the braking portions 11 through energization, respectively. The braking portions 11 have wedges 13, which can move into contact with and away from the car guide rails 2, respectively. The wedges 13 are pressed against the car guide rails 2, respectively, through operation of the braking portions 11, respectively. When the wedges 13 are pressed against the car guide rails 2, respectively, the braking portions 11 thereby generate braking forces applied to the car 3, respectively. The car 3 is forcibly stopped by the braking forces generated through operations of the respective braking portions 11.
The car 3 is also mounted with a pulley device (rotational body device) 17, which has a first driven pulley 14 and a second driven pulley 15 as a pair of rotational bodies rotated in accordance with the speed of the car 3 and an urging device 16 for urging the first driven pulley 14 and the second driven pulley 15 away from each other. In this example, the pulley device 17 is provided on a lower portion of the car 3. The first driven pulley 14 and the second driven pulley 15 are disposed vertically in alignment with each other. That is, the first driven pulley (one of the rotational bodies) 14 is disposed above the second driven pulley (the other rotational body) 15. A governor rope 18 is looped around the first driven rope 14 and the second driven rope 15 so as to surround them together.
An upper fixed member 19 and a lower fixed member 20, which are fixed to the car guide rails 2, respectively, are provided in the upper portion of the hoistway 1 and a lower portion of the hoistway 1, respectively. The governor rope 18 is connected at one end thereof to the upper fixed member 19 via a spring (elastic body) 21. The governor rope 18 is connected at the other end thereof to the lower fixed member 20 via a spring (elasticbody) 22. The governor rope 18, which extends from the lower fixed member 20 side to the upper fixed member 19 side, is looped around the first driven pulley 14 and then around the second driven pulley 15.
A tensile force is applied to the governor rope 18 owing to respective urging forces of the springs 21 and 22 and the urging device 16. Thus, frictional forces are generated between the governor rope 18 and the first driven pulley 14 and between the governor rope 18 and the second driven pulley 15, respectively. As a result, the first driven pulley 14 and the second driven pulley 15 are prevented from slipping with respect to the governor rope 18. The pulley device 17 is moved with respect to the governor rope 18 when the car 3 is raised/lowered within the hoistway 1. The first driven pulley 14 and the second driven pulley 15 are thereby rotated in accordance with the speed of the car 3. In other words, the rotational speeds of the first driven pulley 14 and the second driven pulley 15 increase as the speed of the car 3 increases, and decrease as the speed of the car 3 decreases.
A car shock absorber 23 for absorbing a shock caused to the car 3 upon a fall thereof and a counterweight shock absorber 24 for absorbing a shock caused to the counterweight 4 upon a fall thereof are installed on a bottom portion within the hoistway 1. A control cable (mobile cable) 25 for transmitting information between a control device (not shown) for controlling operation of an elevator and the car 3 is connected to the car 3.
Fig. 2 is a schematic diagram showing an essential part of the elevator apparatus of Fig. 1. Fig. 3 is a lateral view showing the pulley device 17 of Fig. 2. Referring to the figures, the car 3 is mounted with a first generator 26 and a second generator 27 for generating power through movement of the car 3, and a first car speed detector 28 and a second car speed detector 29 for detecting a speed of the car 3. The first generator 26 and the first car speed detector 28 are provided on a rotational shaft of the first driven pulley 14. The second generator 27 and the second car speed detector 29 are provided on a rotational shaft of the second driven pulley 15. The first generator 26 and the first car speed detector 28 may be integrated with the first driven pulley 14 or engaged with an outer peripheral portion of the first driven pulley 14 instead of being provided on the rotational shaft of the first driven pulley 14. The second generator 27 and the second car speed detector 29 may be integrated with the second driven pulley 15 or engaged with an outer peripheral portion of the second driven pulley 15 instead of being provided on the rotational shaft of the second driven pulley 15.
The first generator 26 generates a power corresponding to a speed of the car 3 based on rotation of the first driven pulley 14. The second generator 27 generates a power corresponding to a speed of the car 3 based on rotation of the second driven pulley 15. The respective emergency stop devices 10 are operated by the powers generated by the first generator 26 and the second generator 27 when the speed of the car 3 is abnormal (excessively high) . That is, the magnitudes of the powers generated by the first generator 26 and the second generator 27 increase as the speed of the car 3 increases, so the emergency stop devices 10 do not operate until the magnitudes of the powers generated by the first generator 26 and the second generator 27 reach predetermined values at the time when the speed of the car 3 has abnormally increased.
The first car speed detector 28 generates a signal corresponding to a speed of the car 3 based on rotation of the first driven pulley 14. The second car speed detector 29 generates a signal corresponding to a speed of the car 3 based on rotation of the second driven pulley 15. For example, encoders can be mentioned as the first car speed detector 28 and the second car speed detector 29.
The car 3 is mounted with a speed governing device 30 and a backup circuit 31 for supplying the electromagnetic drive portions 12 with powers from the first generator 26 and the second generator 27 only when the speed of the car 3 is abnormal.
The speed governing device 30 has a power receiving portion 32 for receiving powers from the first generator 26 and the second generator 27, and a speed governing control portion 33 for determining, based on respective pieces of information from the first car speed detector 28 and the second car speed detector 29, whether or not the speed of the car 3 is abnormal, thereby supplying the respective emergency stop devices 10 with the powers received by the power receiving portion 32 only when the speed of the car 3 is abnormal.
The power receiving portion 32 supplies the speed governing control portion 33 with the powers from the first generator 26 and the second generator 27 as a control power source for a control operation of the speed governing device 30 and an emergency operation power source for causing the electromagnetic drive portions 12 of the emergency stop devices 10 to operate.
The speed governing control portion 33 is allowed to perform the control operation by being supplied with the control power source from the power receiving portion 32. The speed governing control portion 33 has a first processing portion 34 for determining, based on information from the first car speed detector 28, whether or not the speed of the car 3 is abnormal, a second processing portion 35 for determining, based on information from the second car speed detector 29, whether or not the speed of the car 3 is abnormal, and an emergency output portion 36 for supplying the respective emergency stop devices 10 with the emergency operation power source from the power receiving portion 32 when at least one of the first processing portion 34 and the second processing portion 35 has determined that the speed of the car 3 is abnormal.
An overspeed setting pattern as a reference for determining whether or not the speed of the car 3 is abnormal, which corresponds to a vertical position within the hoistway 1, is set in advance in each of the first processing portion 34 and the second processing portion 35. In this example, the overspeed setting pattern is set so as to continuously decrease within a predetermined section in the vicinity of each of terminal portions (upper terminal portion and lower terminal portion) of the hoistway 1 as the distance therefrom decreases.
The first processing portion 34 has a first calculation portion 37 for acquiring a signal from the first car speed detector 28 as car information and calculating a position and a speed of the car 3 based on the acquired car information, and a first determination portion 38 for comparing the position and the speed of the car 3 calculated by the first calculation portion 37 with the overspeed setting pattern to determine whether or not the speed of the car 3 is abnormal.
The second processing portion 35 has a second calculation portion 39 for acquiring a signal from the second car speed detector 29 as car information and calculating a position and a speed of the car 3 based on the acquired car information, and a second determination portion 40 for comparing the position and the speed of the car 3 calculated by the second calculation portion 39 with the overspeed setting pattern to determine whether or not the speed of the car 3 is abnormal.
The emergency output portion 36 determines, based on respective pieces of information from the first determination portion 38 and the second determination portion 40, whether or not the respective emergency stop devices 10 should be supplied with the emergency operation power source from the power receiving portion 32. That is, the emergency output portion 36 determines, based on dual determinations, namely, a determination made by the first determination portion 38 and a determination made by the second determination portion 40, whether or not the respective emergency stop devices 10 should be supplied with the emergency operation power source from the power receiving portion 32.
The backup circuit 31 determines, based on magnitudes of powers from the first generator 26 and the second generator 27, whether or not the speed of the car 3 is abnormal, and supplies the electromagnetic drive portions 12 with the powers from the first generator 26 and the second generator 27 only when it is determined that the speed of the car 3 is abnormal. An abnormality determination set value as a reference for determining whether or not the speed of the car 3 is abnormal through a comparison between the magnitudes of the powers from the first generator 26 and the second generator 27 is set in the backup circuit 31. The abnormality determination set value is set higher than a rated speed of the elevator.
When the electromagnetic drive portions 12 are supplied with powers from at least one of the speed governing device 30 and the backup circuit 31, the respective emergency stop devices 10 are thereby operated to forcibly generate braking forces applied to the car 3.
Next, an operation will be described. When the car 3 is moved within the hoistway 1, the first driven pulley 14 and the second driven pulley 15 are rotated in accordance with a speed of the car 3. Thus, powers corresponding to the speed of the car 3 are supplied from the first generator 26 and the second generator 27 to the speed governing device 30 and the backup circuit 31, and signals corresponding to the speed of the car 3 are transmitted from the first car speed detector 28 and the second car speed detector 29 to the speed governing device 30.
The control operation of the speed governing device 30 is performed in response to the supply of powers from the first generator 26 and the second generator 27. Owing to the control operation of the speed governing device 30, the first processing portion 34 determines, based on the signal from the first car speed detector 28, whether or not the speed of the car 3 is abnormal, and the second processing portion 35 determines, based on the signal from the second car speed detector 29, whether or not the speed of the car 3 is abnormal.
In parallel with the determination made by the speed governing device 30, the backup circuit 31 determines, based on the magnitudes of the powers from the first generator 26 and the second generator 27, whether or not the speed of the car 3 is abnormal.
When the elevator is in normal operation and the speed of the car 3 is normal, the respective emergency stop devices 10 are stopped from being supplied with powers from the speed governing device 30 and the backup circuit 31, respectively. Thus, the car 3 is not forcibly stopped through operations of the respective emergency stop devices 10.
For example, when the speed of the car 3 has abnormally increased owing to breakage of the main ropes 9, or the like and at least one of the first processing portion 34 and the second processing portion 35 has determined that the speed of the car 3 is abnormal, the powers generated by the first generator 26 and the second generator 27 are supplied to the respective emergency stop devices 10 from the emergency output portion 36 of the speed governing device 30.
Even in a case where no power is supplied from the speed governing device 30 to the respective emergency stop devices 10, when the backup circuit 31 has determined that the speed of the car 3 is abnormal, the powers generated by the first generator 26 and the second generator 27 are supplied from the backup circuit 31 to the respective emergency stop devices 10.
The magnitudes of the powers supplied to the respective emergency stop devices 10 from each of the speed governing device 30 and the backup circuit 31 are large enough to operate the respective emergency stop devices 10 because the speed of the car 3 has abnormally increased. Accordingly, when the speed of the car 3 has abnormally increased, the respective emergency stop devices 10 are supplied with a power from the speed governing device 30 or the backup circuit 31 to be operated, so the car 3 is stopped from moving.
In the elevator apparatus constructed as described above, the first generator 26 and the second generator 27 generate powers corresponding to the speed of the car 3, and the emergency stop devices 10 are operated by the powers of the first generator 26 and the second generator 27 at the time when the speed of the car 3 is abnormal. Therefore, moving energy of the car 3 can be converted into a power. Even when the speed of the car 3 has abnormally increased in the event of a blackout, powers large enough to operate the respective emergency stop devices 10 can be generated by the first generator 26 and the second generator 27. Accordingly, the emergency stop devices can be prevented from failing to operate for reasons of, for example, a deterioration in a battery, in the event of a blackout. As a result, the emergency stop devices 10 can be operated more reliably in a shorter period of time.
The car 3 is mounted with the first generator 26 and the second generator 27, so the respective emergency stop devices 10 can be prevented from being stopped from being supplied with powers owing to, for example, breakage of the control cable 25. As a result, the respective emergency stop devices 10 can be supplied with powers more reliably.
The first car speed detector 28 and the second car speed detector 29 generate signals corresponding to the speed of the car 3, and the speed governing device 30 determines, based on the signals from the first car speed detector 28 and the second car speed detector 29, whether or not the speed of the car 3 is abnormal. Only when it is determined that the speed of the car 3 is abnormal, the respective emergency stop devices 10 are supplied with powers from the first generator 26 and the second generator 27. Therefore, the respective emergency stop devices 10 can be prevented from malfunctioning. In addition, the respective emergency stop devices 10 can be operated more reliably when the speed of the car 3 is abnormal.
The car 3 is mounted with the first car speed detector 28 and the second car speed detector 29, so signals from the first car speed detector 28 and the second car speed detector 29 can be transmitted to the speed governing device 30 more reliably.
The pulley device 17 has the first driven pulley 14 and the second driven pulley 15, which are rotated in accordance with the speed of the car 3. The speed governing device 30 determines, based on rotation of the first driven pulley 14 and the second driven pulley 15, whether or not the speed of the car 3 is abnormal. Therefore, the determination can be made by the speed governing device 30 more reliably with a simple configuration.
The speed governing device 30 has the first processing portion 34 for determining, based on rotation of the first driven pulley 14, whether or not the speed of the car 3 is abnormal, the second processing portion 35 for determining, based on rotation of the second driven pulley 15, whether or not the speed of the car 3 is abnormal, and the emergency output portion 36 for supplying the emergency stop devices 10 with powers from the first generator 26 and the second generator 27 when at least one of the first processing portion 34 and the second processing portion 35 has determined that the speed of the car 3 is abnormal. Therefore, a plurality of determinations can be made on the presence or absence of an abnormality in the speed of the car 3, and the reliability in determining whether or not the respective emergency stop devices 10 should be supplied with powers can be enhanced. Thus, the emergency stop devices 10 can further be prevented from malfunctioning.
The governor rope 18, which is vertically stretched within the hoistway 1, is looped around the first driven pulley 14 and the second driven pulley 15 so as to surround them together. The first driven pulley 14 and the second driven pulley 15 are urged away from each other by the urging device 16 such that a tensile force is applied to the governor rope 18. Therefore, a large frictional force can be generated between the first driven pulley 14 and the governor rope 18 and between the second driven pulley 15 and the governor rope 18, respectively. As a result, the first driven pulley 14 and the second driven pulley 15 can be prevented from slipping with respect to the governor rope 18. Thus, the first driven pulley 14 and the second driven pulley 15 can be rotated more reliably in accordance with the speed of the car 3.
The governor rope 18 is connected to the upper portion of the hoistway 1 via the spring 21 and to the lower portion of the hoistway 1 via the spring 22, so a tensile force can be applied to the governor rope 18. In addition, even when the length of the governor rope 18 has increased owing to changes over time or the like, the increase in the length of the governor rope 18 can be absorbed by elasticity of the springs 21 and 22. As a result, the frictional forces between the first driven pulley 14 and the governor rope 18 and between the second driven pulley 15 and the governor rope 18, respectively, can be prevented from decreasing.

Embodiment 2

Fig. 4 is a plan view showing an elevator apparatus according to Embodiment 2 of the present invention. Fig. 5 is a front view showing an essential part of a pulley device of Fig. 4. Referring to the figures, the car 3 is mounted with a pulley device (rotational body device) 54. The pulley device 54 is provided in an upper portion of the car 3. The pulley device 54 has a first driven pulley (rotational body) 51 and a second driven pulley (rotational body) 52, which are arranged at an interval in a horizontal direction, and an urging device 53 for urging the first driven pulley 51 and the second driven pulley 52 away from each other.
The first driven pulley 51 is disposed outward of the second driven pulley 52 with respect to the car 3 in the horizontal direction. Two groove portions 51a and 51b, along which the governor rope 18 is looped, are provided in an outer peripheral portion of the first driven pulley 51. A groove portion 52a, along which the governor rope 18 is looped, is provided in an outer peripheral portion of the second driven pulley 52.
The governor rope 18 is looped around the first driven pulley 51 and the second driven pulley 52 so as to surround them together. The governor rope 18, which extends from the lower fixed member 20 side to the upper fixed member 19 side, is looped around the first driven pulley 51 along the groove portion 51a, around the second driven pulley 52 along the groove portion 52a, and then around the first driven pulley 51 again along the groove portion 51b. A tensile force is applied to the governor rope 18 owing to respective urging forces of the springs 21 and 22 and the urging device 53.
The car 3 is also mounted with a first generator 55 and a second generator 56, which generate powers as the car 3 moves. The first generator 55 is provided on a rotational shaft of the first driven pulley 51. The second generator 56 is provided on a rotational shaft of the second driven pulley 52.
The first generator 55 generates a power corresponding to a speed of the car 3 based on rotation of the first driven pulley 51. The second generator 56 generates a power corresponding to a speed of the car 3 based on rotation of the second driven pulley 52. The respective emergency stop devices 10 are operated by the powers generated by the first generator 55 and the second generator 56 when the speed of the car 3 is abnormal. In this example, the first generator 55 is designed as an AC generator for generating a voltage with a frequency corresponding to rotation of the first driven pulley 51. The second generator 56 is designed as an AC generator for generating a voltage with a frequency corresponding to rotation of the second driven pulley 52.
The car 3 is mounted with a speed governing device 57. The speed governing device 57 is allowed to per form a control operation by receiving the powers from the first generator 55 and the second generator 56. The speed governing device 57 determines, based on the frequencies of the voltages (information on the powers) generated by the first generator 55 and the second generator 56, respectively, whether or not the speed of the car 3 is abnormal, and supplies the respective emergency stop devices 10 with the powers generated by the first generator 55 and the second generator 56 only when the speed of the car 3 is abnormal.
The speed governing device 57 has a first processing portion for determining, based on the frequency of the voltage from the first generator 55, whether or not the speed of the car 3 is abnormal, a second processing portion for determining, based on the frequency of the voltage from the second generator 56, whether or not the speed of the car 3 is abnormal, and an emergency output portion for supplying the respective emergency stop devices 10 with the powers from the first generator 55 and the second generator 56 when at least one of the first processing portion and the second processing portion has determined that the speed of the car 3 is abnormal.
That is, the speed governing device 57 is supplied with the powers from the first generator 55 and the second generator 56 not only as a power source for the control operation but also as information (car information) for detecting a speed of the car 3 and determining whether or not the speed of the car 3 is abnormal. Embodiment 2 of the present invention is identical to Embodiment 1 of the present invention in other constructional details.
Next, an operation will be described. When the first driven pulley 51 and the second driven pulley 52 are rotated through a movement of the car 3, powers corresponding to a speed of the car 3 are supplied from the first generator 55 and the second generator 56 to the speed governing device 57.
Thus, the speed governing device 57 determines, based on information on the respective powers from the first generator 55 and the second generator 56 (frequencies of voltages in this example), whether or not the speed of the car 3 is abnormal.
When the elevator is in normal operation and the speed of the car 3 is normal, the speed governing device 57 does not determine that the speed of the car 3 is abnormal, so no power is supplied from the speed governing device 57 to the respective emergency stop devices 10.
For example, when the speed of the car 3 has abnormally increased owing to breakage of the main ropes 9 and the speed governing device 57 has determined that the speed of the car 3 is abnormal, the powers generated by the first generator 55 and the second generator 56 are supplied from the speed governing device 57 to the respective emergency stop devices 10. Thus, the respective emergency stop devices 10 are operated, so the car 3 is stopped from moving.
In the elevator apparatus constructed as described above, the speed governing device 57 acquires the frequencies of the voltages from the first generator 55 and the second generator 56 as information on the powers, determines, based on the information on the powers, whether or not the speed of the car 3 is abnormal, and supplies the respective emergency stop devices 10 with the powers from the first generator 55 and the second generator 56 only when it is determined that the speed of the car 3 is abnormal. Therefore, the speed of the car 3 can be detected without using a dedicated speed detector for detecting the speed of the car 3. Thus, the number of parts can be reduced, so cost reduction and size reduction can be achieved.
The first driven pulley 51 and the second driven pulley 52 are arranged at an interval in the horizontal direction. Therefore, the dimension of the pulley device 54 in a height direction can be reduced, and the dimension of the hoistway 1 in a height direction can be reduced. Thus, the elevator apparatus can be reduced in size .
In the foregoing example, the frequencies of the voltages are used as the information on the powers in order for the speed governing device 57 to detect the speed of the car 3. However, any information changing in accordance with the speed of the car 3 may be used. For example, the magnitudes of the voltages may be used. It is also appropriate to provide loads such as resistors or the like at output portions of the generators from which outputs are transmitted to the speed governing device, thereby using the magnitudes of currents or frequencies as the information on the powers. In this manner as well, the speed governing device 57 can determine whether or not the speed of the car 3 is abnormal, and the dedicated speed detector for detecting the speed of the car 3 can be dispensed with.
In the foregoing respective embodiments of the present invention, two driven pulleys rotated in accordance with the speed of the car 3, namely, the first driven pulley and the second driven pulley are employed. However, only a single driven pulley may be employed. In this manner as well, the speed governing device can calculate a speed of the car 3 based on rotation of the driven pulley and determine whether or not the speed of the car 3 is abnormal. In this case, the governor rope 18 is looped around only the single driven pulley. A tensile force is applied to the governor rope 18 owing to urging forces of the springs 21 and 22.
Further, three or more driven pulleys may be employed. In this case, the speed governing device is provided with three or more processing portions corresponding to the driven pulleys, respectively. Each of the processing portions determines, based on rotation of a corresponding one of the driven pulleys, whether or not the speed of the car 3 is abnormal. The emergency output portion supplies the respective emergency stop devices 10 with powers from the first generator and the second generator when the number of the processing portions having determined that the speed of the car 3 is abnormal is larger than the number of the processing portions having determined that the speed of the car 3 is normal. In a case where, for example, three driven pulleys are employed, the speed governing device supplies the respective emergency stop devices 10 with powers from the generators when two or three processing portions have determined that the speed of the car 3 is abnormal. In this manner, even when an erroneous determination has been made on rotation of one or some of the driven pulleys, it is possible to determine, based on determinations made on the other pulleys, whether to supply the respective emergency stop devices 10 with powers. As a result, the reliability of the determination made by the speed governing device can be enhanced.
In the foregoing respective embodiments of the present invention, the governor rope 18 is connected to the upper portion of the hoistway 1 and the lower portion of the hoistway 1 via the springs 21 and 22, respectively. However, the governor rope 18 may be connected to only the upper portion of the hoistway 1 or the lower portion of the hoistway 1 via a spring. In this manner as well, an increase in the length of the governor rope 18 can be absorbed by the spring, and the magnitude of a frictional force between each of the driven pulleys and the governor rope 18 can be prevented from decreasing.
In the foregoing respective embodiments of the present invention, only the car 3 is mounted with the pulley device, the emergency stop devices, the speed governing device, and the backup circuit. However, the counterweight 4 may be mounted with these components, or both the car 3 and the counterweight 4 may be mounted with these components, respectively.

Claims

An elevator apparatus, comprising: a generator (26,27,55,56) for generating a power corresponding to a speed of a raised/lowered body (3);
an emergency stop device (10) with which the raised/lowered body (3) is mounted, for being operated by the power generated by the generator (26,27,55,56) to forcibly brake the raised/lowered body (3) when the speed of the raised/lowered body (3) is abnormal; characterized by
a speed governing device (57) for acquiring information on the power from the generator (55,56) as raised/lowered body information, determining, based on the raised/lowered body information, whether or not the speed of the raised/lowered body (3) is abnormal, and supplying the emergency stop device (10) with the power from the generator (55,56) only when it is determined that the speed of the raised/lowered body (3) is abnormal; and
a rotational body device (17,54) having a rotational body (14,15,51,52) rotated in accordance with a speed of the raised/lowered body (3), wherein:
the speed governing device (30,57) acquires the raised/lowered body information based on rotation of the rotational body (14,15,51,52),

the rotational body device (17,54) has a plurality of the rotational bodies (14,15,51,52), and

the speed governing device (30,57) makes, based on the raised/lowered body information obtained from rotation of the respective rotational bodies (14,15,51,52), individual determinations on whether or not the speed of the raised/lowered body (3) is abnormal, and supplies the emergency stop device (10) with the power from the generator (26,27,55,56) when at least one of the determinations has produced a result that the speed of the raised/lowered body (3) is abnormal.
An elevator apparatus, comprising: a generator (26,27,55,56) for generating a power corresponding to a speed of a raised/lowered body (3);
an emergency stop device (10) with which the raised/lowered body (3) is mounted, for being operated by the power generated by the generator (26,27,55,56) to forcibly brake the raised/lowered body (3) when the speed of the raised/lowered body (3) is abnormal; characterized by
a speed governing device (57) for acquiring information on the power from the generator (55,56) as raised/lowered body information, determining, based on the raised/lowered body information, whether or not the speed of the raised/lowered body (3) is abnormal, and supplying the emergency stop device (10) with the power from the generator (55,56) only when it is determined that the speed of the raised/lowered body (3) is abnormal; and
a rotational body device (17,54) having a rotational body (14,15,51,52) rotated in accordance with a speed of the raised/lowered body (3), wherein:
the speed governing device (30,57) acquires the raised/lowered body information based on rotation of the rotational body (14,15,51,52),

the rotational body device (17,54) has the three or more rotational bodies (14,15,51,52), and

the speed governing device (30,57) makes, based on the raised/lowered body information obtained from rotation of the respective rotational bodies (14,15,51,52), individual determinations on whether or not the speed of the raised/lowered body (3) is abnormal, and supplies the emergency stop device (10) with the power from the generator (26,27,55,56) when the determinations having produced a result that the speed of the raised/lowered body (3) is abnormal are larger in number than the determinations having produced a result that the speed of the raised/lowered body (3) is normal.
The elevator apparatus according to Claim 1 or 2,characterized in that the information on the power is a magnitude of a voltage.
An elevator apparatus according to Claim 1 or 2, characterized in that the generator (55,56) generates an alternating voltage, and
the speed governing device (57) is supplied from the generator (55,56) with a frequency of the voltage as the information on the power.
An elevator apparatus according to any of the previous claims, characterized in that
the rotational body device (17,54) has a pair of the rotational bodies (14,15,51,52) around which a governor rope (18) connected to an upper portion of a hoistway (1) and a lower portion of a hoistway (1) is looped, and an urging device (16,53) for urging the rotational bodies (14,15,51,52) away from each other,
the raised/lowered body (3) is mounted with the rotational body device (17,54),
the governor rope (18) is looped around the respective rotational bodies (14,15,51,52) so that the governor rope (18) surrounds the respective rotational bodies (14,15,51,52) together, and
the urging device (16,53) urges the respective rotational bodies (14,15,51,52) to apply a tensile force to the governor rope (18).
The elevator apparatus according to Claim 5, characterized in that the respective rotational bodies (51,52) are arranged at an interval in a horizontal direction.
The elevator apparatus according to Claim 5 or 6, characterized in that the governor rope (18) is connected to at least one of the upper portion of the hoistway (1) and the lower portion of the hoistway (1) via an elastic body (21,22).
The elevator apparatus according to any one of Claims 1 to 7, characterized in that the raised/lowered body (3) is mounted with the generator (26,27,55,56).