EP1577247A1

EP1577247A1 - Elevator

Info

Publication number: EP1577247A1
Application number: EP02808321A
Authority: EP
Inventors: Naoki Mitsubishi Denki K. K. HASHIGUCHI
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-12-24
Filing date: 2002-12-24
Publication date: 2005-09-21
Also published as: KR100633950B1; WO2004058619A1; JPWO2004058619A1; KR20040089665A; CN1612837A; EP1577247A4

Abstract

On a frame body (30) provided in the top part of the hoistway (1), a hoisting machine (13) comprising a drive sheave (14) arranged so that the rotary shaft thereof is almost vertical, direction-changing pulleys such as a car-side deflector sheave (15) etc. , a control panel (31), a governor (32), are fixed. An elevator car (5), has an opening (9) for maintenance on the top surface (8) of the car. At least a part of equipments such as the hoisting machine (13) are arranged so as to overlap with the car (5) in the vertical projection view of the hoistway (1), and the space between the hoisting machine (13) and the top surface (8) of the car when stopped in the predetermined position for maintenance is the value obtained by dividing the square of the rated speed of said elevator car by the double of the gravitational acceleration (V²/2g) or more, and is also minimized as much as possible. Furthermore, the maintenance worker (20) performs maintenance of equipments such as the hoisting machine (13) etc. by stretching out his or her hands out of the opening (9) of the upper surface (8) of the car by getting on a workbench (21) inside the car (5).

Description

Technical Field

The present invention relates to an elevator system of which the hoisting machine is provided in an upper part of the hoistway.

Background Art

Most of the "machineroom-less" elevators, which are on the increase in recent years, have a hoisting machine provided in the top part of the hoistway, and in the vertical projection view of the hoistway, a drive sheave of the hoisting machine is arranged between the elevator car and a hoistway wall and the hoisting machine is arranged so that a part thereof overlaps with the car. Also, equipment such as the control panel, the deflector pulleys, and the governor, etc. provided in the machine room in the past are arranged between the elevator car and hoistway walls in the vertical projection view of the hoistway.

In elevator systems of this kind of structure, spaces that are larger than the thickness of equipment including the drive sheave, the control panel, the direction-changing pulleys, the governor and the like, are required between the elevator car and the hoistway walls in the vertical projection view of the hoistway. These spaces become the cause of the dead spaces throughout the hoistway, and especially, the more the buildings become high-rise, the larger these dead spaces become.

Furthermore, in the lengthwise direction of the top part of the hoistway, assuming the possibility of the elevator's ascending to the upper limit due to its running out of control, there would be a necessity to provide a space in the top part of the hoistway in order to avoid collision of the equipment arranged in the top part of the hoistway and the elevator car, and to secure safety for the maintenance worker at maintenance, and for these reasons, a dead space would be generated also in the top part of the hoistway. Here, the dead space would be one of the two following values: the first is a lengthwise space which is provided so that the equipment arranged in the top part of the hoistway do not collide with the elevator car in the event of the car running out of control up to the upper limit ; the other is a lengthwise space which is secured because of the necessity to keep a large space between the elevator car and the equipment arranged in the top part of the hoistway so that the maintenance worker does not hit his or her head on the top of the hoistway or on the equipment arranged in the top part of the hoistway in the case where the elevator car runs out of control. This is because a maintenance worker would get on the top surface of the elevator car to do his or her work to inspect equipment such as the hoisting machine or the like that is arranged in the hoistway in conventional elevators, or, as described in Japanese non-examined laid-open patent publication No. Hei 97357, a maintenance worker would work with his or her body thrust forward out of the car.

As described above, in conventional machineroom-less elevators, a dead space for the whole height of the hoistway and also a dead space for the top part of the hoistway are generated.

In the present invention, the dead space generated for the whole height of the hoistway is minimized by not arranging the equipment such as the hoisting machine etc. between the elevator car and the hoistway walls in the vertical projection view of the hoistway. Furthermore, the dead space provided for avoiding collision of the equipment arranged in the top part of the hoistway and the elevator car, and for securing safety for the maintenance worker in the case where the elevator runs out of control and ascends to the upper limit, is minimized. By these means, this invention has as its object the provision of an elevator system in which the space necessary for the hoistway is minimized.

Disclosure of the Invention

The elevator system in the present invention has a frame body provided in the top part of the hoistway, and on the frame body, a hoisting machine and direction-changing pulleys are fixed. The hoisting machine has a drive sheave which is arranged so that the rotary shaft thereof is almost vertical. The direction-changing pulleys are for changing the direction of the main rope of the elevator which is passed around the drive sheave of the hoisting machine. On the ceiling of the elevator car, there is provided an opening which is openable and closable. Here, the hoisting machine or the direction-changing pulleys is arranged so that at least a part thereof overlaps with the elevator car or the counterweight in the vertical projection view. Also, the space between the hoisting machine and the direction-changing pulleys, and the top surface of the elevator car in the state where the elevator car is stopped at the predetermined position for maintenance, is defined to be at least (V²/2g), which is the value obtained by dividing the square of the rated speed of the elevator car by the double of gravitational acceleration, or more, and is also minimized.

Furthermore, on the frame body, a control panel or a governor for controlling the ascent and descent of the elevator car, and it is arranged so that at least a part of the control panel or the governor overlaps with the elevator car in the vertical projection view.

In the elevator system structured in the aforementioned manner, the space between the control panel or the governor and the top surface of the elevator car in the state where the elevator car is stopped at the predetermined position for maintenance is defined to be at least (V²/2g), which is the value obtained by dividing the square of the rated speed of the elevator car by the double of gravitational acceleration or more, and is also minimized.

Further, at least one of the surfaces of the hoisting machine and the control panel that are subject to maintenance is arranged in the vertical downward side.

Moreover, the hoisting machine is formed so that the thickness in the direction of the rotary shaft thereof is smaller than the dimension in the radial direction.

According to the above-mentioned invention, it is possible to obtain an elevator system wherein the space required for the hoistway is minimized by minimizing the dead space generated between the elevator car and the surfaces of the side walls of the hoistway throughout the whole height of the hoistway by arranging to gather the equipments such as the hoisting machine etc. in the top part of the hoistway, and the dead space provided for avoiding collision of the equipments provided in the top part of the hoistway and the elevator car and for securing safety for the maintenance worker.

Brief Description of the Drawings

Figure 1 shows an example of an arrangement of an elevator system in accordance with the embodiment of the present invention, and is a plan view of the elevator system viewed from above;

Figure 2 is a rear view of the elevator system in Figure 1 viewed from the rear side of the hoistway;

Figure 3 is a side view of the elevator system in Figure 1 viewed from a side, and is a drawing explaining the method of the maintenance work;

Figure 4 is a conceptual drawing for explaining the motion of the elevator car of the present invention when running out of control, on the assumption of a state in which the elevator car runs out of control, in the elevator system in accordance with the embodiment of the present invention; and

Figure 5 is a drawing for explaining the method of the maintenance work for an elevator of a high rated speed, in the elevator system in accordance with the embodiment of the present invention.

Best Mode for Carrying out the Invention

To describe the present invention in more detail, the invention will be described by referring to the accompanying drawings. In each of the drawings, the same numerals are given to the same parts or the corresponding parts, and repeated explanation will be appropriately simplified or omitted.

Figure 1 shows an example of an arrangement of an elevator system in accordance with the present invention, and is a plan view of the elevator system viewed from above. Figure 2 is a rear view of the elevator system in Figure 1 viewed from the rear side of the hoistway.

In the figures, inside the hoistway 1, there are provided a pair of guiderails 3 for an elevator car and another pair of guiderails 4 for a counterweight, via rail brackets (not shown) provided on the walls 2 of the hoistway 1. The elevator car 5 ascends and descends through the hoistway 1 being guided by the guiderails 3 for the car, and the counterweight 10 ascends and descends through the hoistway 1 being guided by the guiderails 4 for the counterweight, in the direction opposite to the car 5.

In the front side of the elevator car 5, there is provided an entrance doors 7. In the following explanation on Figure 1, the surface of the wall facing the entrance doors 7 will be called 'the front side' , and the surface of the wall opposite to the front side will be called 'the rear side'. In addition to this, both the surfaces of the walls which are orthogonal to the surface of the entrance doors will be called 'the sides'. Further, the bottom surface and the both the side surfaces of the car 5 are supported by a car frame 6 formed from a plurality of beams. Here, on the top surface 8 of the car 5, an opening 9 for maintenance work, which is openable and closable by means of an opening/closing lid 9a, is provided. The counterweight 10 is provided behind the car 5 in the hoistway 1, and also one of the sides thereof is arranged near the wall 2 of the hoistway 1.

Next, in the top part of the hoistway 1, a frame body 30 which is supported by guiderails 3 for the car and guiderails 4 for the counterweight are provided. On the frame body 30, a hoisting machine 13 having a drive sheave 14 around which the elevator main rope 12 is passed is provided. The drive sheave 14 is arranged so that the rotary shaft thereof is almost vertical. The hoisting machine 13 is provided so that at least a part thereof and the car 5 overlap with each other in the hoistway 1 in the vertical projection view. In the arrangement example shown in Figure 1, the hoisting machine 13 is arranged at a different corner part of the car 5 at the other side from the corner part where the counterweight 10 is arranged, with, in the vertical projection view of the hoistway 1, the main part thereof overlapping with the car 5, and also partially with the opening 9 of the top surface 8 of the car 5. The hoisting machine 13 is formed so that the thickness in the direction of the rotary shaft thereof is smaller than the dimension in the radial direction.

Next, the direction-changing pulleys used in this embodiment indicate the car-side deflector sheave 15, counterweight-side deflector sheave 16, car pulleys 17 and the counterweight pulley 18. Explanation on these direction-changing pulleys will be given successively together with explanation on the roping route of the main rope 12 passed around the drive sheave 14 of the hoisting machine 13. One of the ends of the main rope 12 is passed around the car-side deflector sheave 15; the direction thereof is changed from the horizontal direction to the vertical direction; is passed around the car pulleys 17 provided on both sides of the lower part of the car frame 6 one by one; and again the direction thereof is changed from the horizontal direction to the vertical direction; and is engaged to the frame body 30 in the top part of the hoistway 1. The other end of the main rope 12 is passed around the counterweight-side deflector sheave 16 from the hoisting machine 13; the direction thereof is changed from the horizontal direction to the vertical direction; is passed around the counterweight pulley 18; and is engaged to the frame body 30 in the top part of the hoistway 1. Here, the car-side deflector sheave 15 and the car pulleys 17 are arranged so that at least a part of them overlaps the car 5 in the vertical projection view of the hoistway 1. That is, as the main rope part in the direction from the car-side deflector sheave 15 to the car pulleys 17 and the main rope part in the direction from the car pulleys 17 to the frame body 30 are arranged in a position that is as close as possible to the side of the car 5, a large part of the car-side deflector sheave 15 and the car pulleys 17 overlap with the car 5 in the vertical projection view, and therefore, it is not necessary to keep a long distance between the car 5 and the hoistway walls 2. The car-side deflector sheave 15 is arranged so as to overlap with the opening 9 of the top surface 8 of the car. Also the counterweight-side deflector sheave 16 is arranged to overlap with the counterweight 10 at least partially with the counterweight 10 in the vertical projection view of the hoistway 1, and the counterweight pulley 18 is arranged so as to entirely overlap with the counterweight 10 in the vertical projection view of the hoistway 1. That is, there is no necessity to leave a large space between the counterweight 10 and the elevator car 5.

Next, the control panel 31 for controlling the ascent and descent of the elevator car 5 is arranged so that at least a part thereof overlaps the car 5 in the vertical projection view of the hoistway 1. In the arrangement example in Figure 1, the entire control panel 30 is arranged so as to overlap with the car 5, and also with the opening 9 of the top surface 8 of the car in the vertical projection view.

Next, the governor 32 is, similarly to the control panel 31, provided on the frame body 30 in the upper part of the hoistway 1, and has a governor rope 33 wound around itself. Also, a governor rope tension sheave 34 for applying tension to the governor rope 33 is provided in the lower part of the hoistway 1. Also the governor 32 is, similarly to the control panel 31, arranged so that at least a part thereof overlaps with the elevator car 5 in the vertical projection view. A part of the governor 32 overlaps with the opening 9 of the top surface 8 of the car. That is, except for the sheave part of the governor 32, equipment are arranged to overlap with the car 5, and there is no necessity to take a useless space between the governor 32 and the car 5 due to the thickness of the governor 32.

As explained above, in this embodiment, equipments provided in the top part of the hoistway such as the hoisting machine 13, the car-side deflector sheave 15, the counterweight-side deflector sheave 16, the control panel 31, the governor 32, etc. are arranged gathered on the frame body 30 (in this description, 'equipments provided in the top part of the hoistway' refers to the hoisting machine 12, the car-side deflector sheave 15, the counterweight-side deflector sheave 16, the control panel 31 and the governor 32). In the above-mentioned explanation, an example that the frame body 30 is supported by the car guiderails 3 and the counterweight guiderails 4 is described, however, it can also be supported by the walls 2 of the hoistway 1.

Figure 3 is a side view of the elevator system viewed from the side, and is a drawing for explaining the method of maintenance work.

Explanation on the method of maintenance of the elevator system will be given referring to Figure 3. Firstly, the elevator car 5 is stopped at the predetermined maintenance position near the uppermost floor, and the maintenance worker 20 gets on the workbench 21, opens the opening/closing lid 9a of the opening 9 of the upper surface 8 of the car, and does the work of inspecting the equipments provided in the top part of the hoistway. The workbench 21 used here is permanently installed and foldable, and is folded housed in an inside surface of a side wall in the car during normal operation of the elevator. The workbench 21 has a mechanism of adjusting the height thereof in the up and down directions, and the height is adjusted according to the height of the worker 20. The surfaces 22 of the hoisting machine 13 and the control panel 31 which are subject to maintenance is arranged in the vertical downward side. In this invention, as the aim is to make the dead space in the top part of the hoistway 1 as small as possible, there is the necessity to lessen the space between the upper surface 8 of the car and the equipments provided in the top part of the hoistway as much as possible, thus calculation of the distance between the top surface 8 of the car and the equipments provided in the top part of the hoistway is carried out in the manner explained as follows.

Figure 4 is a conceptual drawing for explaining the motion of the elevator car, assuming that the elevator car runs out of control, and Figure 4 (A) is a drawing showing the moment the elevator ascends at the rated speed and the counterweight collides with a buffer. Figure 4 (B) is a drawing showing the limit position of the elevator car when further ascended by inertial force after colliding with the buffer.

During ascent at the rated speed, it is necessary to keep a space between the top surface 8 of the car 5 and the equipments provided in the top part of the hoistway in order to avoid collision against each other, assuming the possibility of the car's 5 running out of control due to some cause. In other words, the distance between the top surface 8 of the car 5 and the equipments provided in the top part of the hoistway should be the distance that the car 5 does not collide the equipments provided in the top part of the hoistway, or longer in the event that the car 5 runs out of control.

Here, as shown in Figure 4(A), in the case where the elevator car 5 continues ascending during ascent in the rated speed (V) due to some cause, the counterweight 10, which continues descending in the direction opposite to the car 5, collides the buffer 11. As shown in Figure 4(B), because of this collision, the tension of the main rope 12, which had until then been generated, is lost. At this time, the car 5, which had been ascending at the rated speed (V), springs up with this rated speed (V) as the initial speed. The amount of spring can be calculated using the following equation: S=V2/2g

Here, (S) denotes the amount of spring of the car, (V) denotes the initial speed (rated speed) of the car, and (g) denotes gravitational acceleration.

Therefore, by setting as the distance between the upper surface 8 of the car and the equipments provided in the top part of the hoistway an amount which is at least the amount of spring (S) or longer, in the event that the car 5 runs out of control during ascent in the rated speed, it is possible to avoid a situation where collision of the car 5 with the equipments provided in the top part of the hoistway occurs. However, on the other hand, in order to shorten the dead space in the top part of the hoistway, it is required to minimize this distance as much as possible in addition to securing a distance enough for avoiding collision of the upper surface 8 of the car and the equipments provided in the top part of the hoistway when the car runs out of control. For this reason, as the space obtained by the above-described equation is the amount of spring (S) beginning from the position where the counterweight 10 collides the buffer 11, in order to minimize this space, it is preferable to set the maintenance position to where the maintenance worker 20 moves the car 5 for maintenance work a position just before the counterweight 10 comes into contact with the buffer 11. In fact, there is the necessity of providing room between the counterweight 10 and the buffer 11, however, it would be enough to take about 20% of the amount of spring (S) of the car 5 as the room.

According to the above, the space at the maintenance position between the top surface 8 of the car and the equipments provided in the top part of the hoistway will be enough when set at a distance between the amount of spring (S) to the distance which is about 20% more than the amount of spring (S). For example, to actually calculate the distance for an elevator of the rated speed of 120 m per minute, the amount of spring (S) is about 20 cm, and taking the room into consideration, it would be enough to secure about 20 to 24 cm as the space. Thus, as shown in Figure 3, at maintenance work, the maintenance worker 20 can avoid hitting his or her head on the equipments provided in the top part of the hoistway by not poking his or her head out of the opening 9 of the upper surface 8 of the car, but by setting the height of the workbench 21 at a height that would allow his or her hands to reach the equipments provided in the top part of the hoistway such as the hoisting machine 13, in the event that the car 5 drives out of control.

Next, Figure 5 is a drawing for explaining the method of maintenance work for an elevator of a high rated speed.

In 'high-speed elevators', of which the rated speed is higher than 120 m per minute, the aforementioned amount of spring (S) of the car 5 becomes larger in proportion to the square of the speed, thus the minimum space required between the top surface 8 of the car and the equipments provided in the top part of the hoistway becomes longer as the rated speed of the elevator increases. Even in these cases, as shown in Figure 5, it is possible for the maintenance worker 20 to carry out the maintenance work by poking his or her head out of the opening 9 of the top surface 8 of the car and by adjusting the height of the workbench 21 so that his or her hands will reach the equipments provided in the top part of the hoistway such as the hoisting machine 13, and in the event that the car 5 runs out of control, the maintenance worker 20 can avoid hitting his or her head to the equipments by merely ducking his or her head.

Moreover, in this embodiment, a workbench 21 which is permanently installed in the car 5 is described as an example, however, the workbench 21 does not have to be limited to a permanently installed type, and can also be brought in from outside for maintenance work. Also, in the figure, the maintenance worker 20 is working standing, however, it is obvious that it is also effective to have the maintenance worker 20 work sitting by raising the height of the workbench 21 more.

According to the above-described embodiment, the following effects can be attained:

By not arranging equipment between the hoistway walls 2 and the elevator car 5 in the vertical projection view by gathering the equipments provided in the top part of the hoistway such as the hoisting machine 13, the car-side deflector sheave 15, the counterweight-side deflector sheave 16, the control panel 31, the governor 32, etc. on the frame body 30, and by arranging the equipments provided in the top part of the hoistway to at least partially overlap with the car 5 or the counterweight 10 in the vertical projection view, the plan dimension of the hoistway 1 becomes minimum, thus making it possible to minimize the dead space throughout the whole height of the hoistway 1. Furthermore, as the equipments provided in the top part of the hoistway overlap with the opening 9 of the top surface 8 of the car in vertical projection view in addition to at least a part of the equipments provided in the top part of the hoistway overlapping the car 5 or the counterweight 10, it becomes easier for the maintenance worker 20 to reach out his or her hands to the subject of maintenance when carrying out maintenance work from inside the car 5, thus improving workability as well.

Furthermore, as the space between the top part of the hoistway 1 and the top surface 8 of the elevator car 5 is set to be the minimum along with making it able to avoid collision of the elevator car 5 and the equipments provided in the top part of the hoistway when the elevator runs out of control, it is possible to minimize the dead space in the top part of the hoistway 1. In addition to this, along with the surface 22 of the hoisting machine 13 and the control panel 31, which is the subject of maintenance, being arranged in the vertical downward side, it is possible to maintain the equipments provided in the top part of the hoistway if the maintenance worker 20 reaches his or her hands out of the opening 9 of the top surface 8 of the car on a workbench 21 without poking his or her head out, or if necessary, poking only his or her head out of the opening 9 of the top surface 8 of the car and reaching out his or her hands, and in the event that the car 5 runs out of control, it is possible to avoid collision of the head of the maintenance worker 20 and the car 5 if the maintenance worker 20 just ducks his or her head, thus making it possible to secure safety for the maintenance worker 20. Due to this, it is possible to shorten the dead space which has heretofore been necessary for securing safety at maintenance work.

Moreover, the hoisting machine 13 is formed so that its thickness in the direction of the rotary shaft thereof is smaller than the dimension in the radial direction, thus contributing to the shortening of the whole height of the hoistway 1.

Furthermore, as the elevator car 5 explained in this embodiment is arranged so that it ascends and descends being supported by the car pulleys 17 that are provided in the lower part of the car frame 6, there is no necessity to provide an upper beam on the top surface 8 of the car, thus contributing to the shortening of the whole height of the hoistway 1. The same effects can be attained also in roping arrangements other than the 2:1 roping arrangement, provided that the elevator does not require an upper beam on the top surface 8 of the car, like elevators of the type which suspend the elevator car 5 from both sides thereof.

According to the above, it is possible to minimize the dead spaces existing in machineroom-less elevators, and also to minimize the spatial volume of the hoistway 1.

Industrial Applicability

As mentioned above, in the elevator system according to the present invention, the dead spaces which have heretofore been existing in the hoistway of conventional machineroom elevators can be minimized, thus it is possible to provide an elevator system even more improved in saving space, which is a merit of machineroom-less elevators. Also, it is possible to economize building cost of the building, and to provide an elevator to be installed under strict conditions such as limits to the exterior or the height of the building.

Claims

An elevator system comprising:

a frame body provided in a top part of a hoistway;

a hoisting machine fixed to said frame body and has a drive sheave arranged so that the rotary shaft thereof becomes almost vertical;

direction-changing pulleys fixed to said frame body and changes the direction of the elevator main rope passed around said drive sheave of said hoisting machine; and

an elevator car provided with an openable/closable opening on the top surface thereof; wherein:

at least a part of said hoisting machine or said direction-changing pulleys is arranged to overlap with either of said elevator car or said counterweight in the vertical projection view of the hoistway;

a space between said hoisting machine and said direction-changing pulleys, and top surface of said elevator car stopped in the predetermined position for maintenance, is the value obtained by dividing the square of the rated speed of said elevator car by the double of the gravitational acceleration (V²/2g) or more, and is also minimized as much as possible.
The elevator system according to claim 1, characterized in that:

a control panel for controlling ascent and descent of said elevator car is fixed onto said frame body;

at least a part of said control panel is arranged to overlap with said elevator car in the vertical projection view of the hoistway; and

a space between said control panel and said top surface of said elevator car stopped in the predetermined position for

maintenance is the value obtained by dividing the square of the rated speed of said elevator car by the double of the gravitational acceleration (V²/2g) or more, and is also

minimized as much as possible.
The elevator system according to claim 1 or 2, characterized in that:

a governor is fixed onto said frame body;

at least a part of said governor is arranged to overlap with said elevator car in the vertical projection view of the hoistway; and

a space between said governor and said top surface of said elevator car stopped in the predetermined position for maintenance is the value obtained by dividing the square of the rated speed of said elevator car by the double of the gravitational acceleration (V²/2g) or more, and is also minimized as much as possible.
The elevator system according to any one of claims 1 through 3, characterized in that at least one of the surfaces of said hoisting machine and said control panel that are subject to maintenance is arranged in the vertical downward side.
The elevator system according to any one of claims 1 through 4, characterized in that said hoisting machine is formed so that the thickness in the direction of the rotary shaft thereof is smaller than the dimension in the radial direction.
The elevator system according to any one of claims 1 through 5, characterized in that said frame body is supported by either the elevator car guiderails and the counterweight guiderails, or the hoistway walls.