EP1497215B1

EP1497215B1 - Elevator main rope elongation compensating apparatus

Info

Publication number: EP1497215B1
Application number: EP02707287A
Authority: EP
Inventors: Aernoud Mitsubishi Elevator Europe B.V. BROUWERS; Wouter Mitsubishi Elevator Europe B.V KEMPES
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-04-01
Filing date: 2002-04-01
Publication date: 2011-11-09
Anticipated expiration: 2022-04-01
Also published as: EP1497215A1; JP4261368B2; WO2003082722A1; CN1304266C; EP1497215A4; CN1491180A; JP2005521610A

Abstract

In an elevator main rope elongation compensating apparatus, an extension portion is mounted to a lower portion of a counterweight. The extension portion projects downward from the lower portion of the counterweight. The extension portion includes one or more movable spacers (15). Each of the movable spacers (15) is movable between a contact position directly above a counterweight buffer (9) and a non-contact position outside a region directly above the counterweight buffer (9). A counterweight overtravel space is adjusted by moving the movable spacers (15) to the non-contact position.

Description

TECHNICAL FIELD

The present invention relates to a main rope elongation compensating apparatus disposed in an elevator apparatus in which a car and a counterweight are suspended inside a hoistway by a main rope, the main rope elongation compensating apparatus compensating for elongation of the main rope.

BACKGROUND ART

An elevator apparatus according to the preamble of claim 1 already known e.g. from JP-A-2000255940 .
Generally, on installation of an elevator apparatus, main ropes require time to settle to the load of a car and a counterweight. In other words, an initial elongation arises in the main ropes immediately after installation. Furthermore, space is reserved in a hoistway to allow for the elongation of the main ropes.
In answer to this, pretensioned ropes in which initial elongation is forcibly generated by applying a tensile load before installation are conventionally known. Initial elongation immediately after installation is decreased by pretensioned ropes of this kind.
Another method is to use types of rope having reduced elongation, but in that case, other problems arise such as the service life of the main ropes being shortened or the strength of the main ropes being reduced. Whatever type of rope is used, including pretensioned ropes, elongation of the main ropes cannot be eliminated completely.
Normally, the car and the counterweight are raised and lowered within a limited raising and lowering zone, but if a malfunction, etc., occurs, the car or the counterweight may move beyond the normal raising and lowering zone. In preparation for such cases, a car buffer is normally installed below the car inside the hoistway, and a counterweight buffer is installed below the counterweight.
Furthermore, space for car overtravel is reserved between the car and the car buffer to allow for errors in landing position when the car is positioned at the lowest floor. Similarly, space for counterweight overtravel (hereinafter "counterweight overtravel space") is reserved between the counterweight and the counterweight buffer for when the car is positioned at an uppermost floor.
However, when elongation arises in the main ropes, the counterweight overtravel space when the car is positioned at the uppermost floor is reduced.
Hence, one method is to add an expected amount of elongation of the main ropes to the counterweight overtravel space. However, with this method, because the car is moved to a higher position proportionate to the expected amount of elongation if the counterweight collides with the counterweight buffer when the main ropes have not yet elongated, it is necessary to increase the size of a top portion space of the hoistway proportionately, increasing the vertical dimensions of the entire hoistway.
In answer to this, another known method for adjusting the counterweight overtravel space is to adjust the height of the counterweight buffer by disposing a plurality of spacer plates under the counterweight buffer. In this method, the spacer plates are removed one by one during maintenance in response to the elongation of the main ropes. Furthermore, in EP 0663367 Bl , for example, a method is described for adjusting the height of the counterweight buffer by means of a screw mechanism in response to the elongation of the main ropes.
However, with these methods, it is necessary for maintenance personnel to measure changes in the position of the counterweight due to the elongation of the main ropes and to enter the hoistway pit to adjust the height dimensions of the counterweight, making the measurement and adjustment operations time-consuming.

DISCLOSURE OF THE INVENTION

The present invention aims to solve the above problems and an object of the present invention is to provide an elevator main rope elongation compensating apparatus capable of adapting easily to elongation of main ropes while preventing increases in vertical dimensions of a hoistway.
According to one aspect of the present invention, there is provided an elevator main rope elongation compensating apparatus disposed in an elevator apparatus including: a hoistway; a car; a counterweight; a main rope suspending the car and the counterweight inside the hoistway; and a counterweight buffer installed below the counterweight inside the hoistway, the elevator main rope elongation compensating apparatus compensating for changes in a distance between the counterweight and the counterweight buffer due to elongation of the main rope, wherein an extension portion is mounted to a lower portion of the counterweight, the extension portion having a movable spacer movable between a contact position directly above the counterweight buffer and a non-contact position outside a region directly above the counterweight buffer.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a general block diagram showing an elevator apparatus according to Embodiment 1 of the present invention;
Figure 2 is a front elevation showing an extension portion and a counterweight buffer from Figure 1 partially sectioned;
Figure 3 is a cross section taken along line III - III in Figure 2;
Figure 4 is a cross section showing part of Figure 2 enlarged;
Figure 5 is a front elevation showing an elevator main rope elongation compensating apparatus according to Embodiment 2 of the present invention partially sectioned;
Figure 6 is a partial cross section taken along line VI - VI in Figure 5;
Figure 7 is a cross section showing a portion of Figure 5 enlarged;
Figure 8 is a cross section showing part of a main rope elongation compensating apparatus according to Embodiment 3 of the present invention; and
Figure 9 is a front elevation showing a main rope elongation compensating apparatus according to Embodiment 4 of the present invention partially sectioned.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present invention will now be explained with reference to the drawings.

Embodiment 1

Figure 1 is a general block diagram showing an elevator apparatus according to Embodiment 1 of the present invention. In the figure, a hoisting machine 2 and a deflection sheave 3 are disposed in an upper portion of a hoistway 1. The hoisting machine 2 has a drive sheave 2a. A plurality of main ropes 4 are wound around the drive sheave 2a and the deflection sheave 3.
An elevator car 5 is suspended by first end portions of the main ropes 4. A counterweight 6.is suspended by second end portions of the main ropes 4. An extension portion 7 being a main rope elongation compensating apparatus for compensating for elongation of the main ropes 4 is mounted to a lower portion of the counterweight 6. The extension portion 7 projects downward from the lower portion of the counterweight 6.
A car buffer 8 is installed on a bottom portion of the hoistway 1 below the car 5. A counterweight buffer 9 is installed on a bottom portion of the hoistway 1 below the counterweight 6. A guard screen 10 is disposed in a lower portion inside the hoistway 1. When the car 5 moves to an uppermost position, the counterweight 6 moves to a lowermost position and is positioned behind the guard screen 10.
Furthermore, it is not possible to access the extension portion 7 without removing the guard screen 10. In addition, a large portion of the counterweight buffer 9 is also disposed behind the guard screen 10.
Figure 2 is a front elevation showing the extension portion 7 and the counterweight buffer 9 from Figure 1 partially sectioned, and Figure 3 is a cross section taken along line III - III in Figure 2. The counterweight 6 is guided by a pair of counterweight guide rails 11 so as to be raised and lowered. The extension portion 7 has: first and second support brackets 12 and 13 mounted to a lower portion of the counterweight 6; a plurality of guide rods 14 being guide members fixed horizontally between the support brackets 12 and 13; a plurality of plate-shaped movable spacers 15 supported and guided by the guide rods 14; contact-position locking devices 21; and non-contact-position locking devices 31.
Each of the movable spacers 15 is movable horizontally between a contact position directly above the counterweight buffer 9 and a non-contact position outside a region directly above the counterweight buffer 9. Furthermore, pairs of stoppers 16 projecting upward are disposed on each of the movable spacers 15 on an end portion nearest to the second support bracket 13. Each pair of stoppers 16 prevents movement of the movable spacer 15 immediately above to the non-contact position until the movable spacer with the stopper moves to the non-contact position.
Figure 4 is a cross section showing part of Figure 2 enlarged. Engaging portions 17 are disposed in the first support bracket 12. A hook 18 is disposed on each of the movable spacers 15 on an end portion nearest to the first support bracket 12. The hooks 18 have recess portions 18a engaged by the engaging portions 17. The hooks 18 are pivotable between a locked position and a released position about a shaft 19.
Engagement of the recess portions 18a by the engaging portions 17 is released by pivoting the hooks 18 counterclockwise from the locked position in Figure 4. Lock holding springs 20 for forcing the hooks 18 into the locked position are disposed on the movable spacers 15.
The contact-position locking devices 21 for locking the movable spacers 15 in the contact position each include an engaging portion 17, a hook 18, a shaft 19, and a lock holding spring 20. Furthermore, when moved to the non-contact position, the movable spacers 15 are locked in the non-contact position by means of the non-contact-position locking devices 31.
In an elevator apparatus of this kind, since the extension portion 7 is disposed on the lower portion of the counterweight 6, if the counterweight 6 moves below a lowermost lowering position, the movable spacers 15 on the extension portion 7 collide with the counterweight buffer 9. Consequently, the distance between the movable spacers 15 and the counterweight buffer 9 when the car 5 moves to an uppermost floor is the counterweight overtravel space.
Initially, all of the movable spacers 15 are disposed so as to be aligned in the contact position. From this state, the movable spacers 15 can each be slid to the non-contact position by pivoting the corresponding hook 18 counterclockwise to the lock holding spring 20 to release the lock held by the contact-position locking device 21. This kind of release or movement operation can be performed easily using a jig, etc.
If elongation arises in the main ropes 4, reducing the counterweight overtravel space, movable spacers 15 can be moved to the non-contact position in response to the reduced dimensions. Since movable spacers 15 that have been moved to the non-contact position are outside a relative path of the counterweight buffer 9, the counterweight overtravel space can be widened by moving the movable spacers 15 to the non-contact position.
Hence, the main rope elongation compensating apparatus according to Embodiment 1 enables the elongation of the main ropes 4 to be adapted easily while preventing increases in the vertical dimensions of the hoistway 1 by mounting the extension portion 7 to the lower portion of the counterweight 6.
Furthermore, because the stoppers 16 are disposed on the movable spacers 15, the movable spacers 15 can be moved to the non-contact position sequentially from the bottom up, preventing intermediate movable spacers 15 from being moved first by mistake.
In addition, because the non-contact-position locking devices 31 are provided, movable spacers 15 that have been moved to the non-contact position will not be moved back to the contact position by vibration, etc.
Moreover, in the above example, the hooks 18 were mounted to the movable spacers 15, but the hooks 18 may also be mounted to the first support bracket 12.

Embodiment 2

Figure 5 is a front elevation showing an elevator main rope elongation compensating apparatus according to Embodiment 2 of the present invention partially sectioned, Figure 6 is a partial cross section taken along line VI - VI in Figure 5, and Figure 7 is a cross section showing a portion of Figure 5 enlarged.
In the figures, the extension portion 7 further includes compressed springs 22 each functioning as a forcing means for forcing a movable spacer 15 to the non-contact position. The compressed springs 22 are disposed between the first support bracket 12 and the movable spacers 15. The compressed springs 22 are coil springs, the guide rods 14 being inserted through the inside thereof. When the lock held by a contact-position locking devices 21 is released, the corresponding movable spacer 15 is pressed by the compressed springs 22 and moved automatically to the non-contact position.
An L-shaped mount member 23 is fixed to a stationary portion inside the hoistway 1, for example, to a base portion of the counterweight buffer 9. A release lever 25 pivotable about a shaft 24 is mounted to an upper end portion of the mount member 23. The release lever 25 is pivotable between a first position shown in Figure 7 and a second position pivoted clockwise from the first position in the figure. A release lever spring 26 for forcing the release lever 25 into the first position is disposed between the mount member 23 and the release lever 25.
A lock release device 27 according to Embodiment 2 includes the mount member 23, the shaft 24, the release lever 25, and the release lever spring 26. The lock release device 27 engages the contact-position locking devices 21 if the counterweight 6 is lowered due to the elongation of the main ropes 4, releasing the lock held by each of the contact-position locking devices 21 sequentially .
A main rope elongation compensating apparatus according to Embodiment 2 includes the extension portion 7 and the lock release device 27. The rest of the construction is similar to that of Embodiment 1.
In a main rope elongation compensating apparatus of this kind, if the counterweight overtravel space is reduced by the elongation of the main ropes 4, a hook 18 is moved below the release lever 25, as shown in Figure 7, when the car 5 moves to the uppermost floor. The hook 18 and the release lever 25 are disposed in mutually-obstructing positions, but because the release lever 25 pivots counter to the release lever spring 26 to the second position when pressed by the hook 18, the hook 18 is able to pass downward. After passage of the hook 18, the release lever 25 is restored to the first position by means of the release lever spring 26.
Then, when the counterweight 6 is raised, the hook 18 comes into contact with the release lever 25 again, but because the release lever 25 cannot pivot counterclockwise from the first position in the figure, this time the hook 18 is pivoted counter to the lock holding spring 20 to the released position. Hence, the lock held by the contact-position locking device 21 is released, whereby the movable spacer 15 is pressed by the compressed spring 22 and moved automatically to the non-contact position.
In a main rope elongation compensating apparatus of this kind, since movement of the movable spacers 15 to the non-contact position is performed automatically, the elongation of the main ropes 4 can be adapted even more easily.
Moreover, the stationary portion inside the hoistway 1 is not limited to the base portion of the counterweight buffer 9, and may be, for example, a counterweight guide rail 11, a rail bracket (not shown), a wall portion of the hoistway 1, etc.

Embodiment 3

Figure 8 is a cross section showing part of a main rope elongation compensating apparatus according to Embodiment 3 of the present invention. In the figure, a detection switch 28 being a lock release detector portion is mounted to the mount member 23. The detection switch 28 is activated when the release lever 25 is pivoted to the second position (double-dotted chain lines in the figure), outputting a detection signal. Here, a micro switch is used for the detection switch 28.
A main rope elongation compensating apparatus according to Embodiment 3 includes the extension portion 7, the lock release device 27, and the detection switch 28. The rest of the construction is similar to that of Embodiment 2.
In a main rope elongation compensating apparatus of this kind, the detection switch 28 is activated when the release lever 25 is pivoted from the first position to the second position, outputting a detection signal. Hence, the release of the lock held by a contact-position locking device 21 is detected beforehand. The detection signal is sent to a monitoring center, for example, where adjusted information concerning the counterweight overtravel space may be displayed on a monitor, stored as maintenance information data, etc.
Moreover, in the above example, the detection switch 28 is disposed on the lock release device 27, but it may also be disposed on a contact-position locking device 21. For example, a detection switch may be disposed so as to detect the pivoting of a hook 18, or a detection switch may be disposed so as to directly detect movement of a movable spacer 15 to the non-contact position.
Furthermore, in the above example, a micro switch is used for the lock release detector portion, but the present invention is not limited to this configuration, and for example, an electrostatic proximity switch, a reflection-type optical switch, an interruption-type optical switch, etc., may also be used.

Embodiment 4

Figure 9 is a front elevation showing a main rope elongation compensating apparatus according to Embodiment 4 of the present invention partially sectioned. In the figure, the non-contact-position locking devices 31 each include: an engaging portion 32 disposed on the second support bracket 13; a hook 33 pivotable between a locked position and a released position for engaging with the engaging portions 32; and a lock holding spring 34 for forcing the hook 33 into the locked position.
A mount plate 35 is mounted to the counterweight guide rails 11. A lowering detection switch 36 is mounted to the mount plate 35. A cam 37 is disposed on an actuator portion of the lowering detection switch 36. The cam 37 is pressed by the hooks 33 of the non-contact-position locking devices 31 when the extension portion 7 descends to a preset position due to the elongation of the main ropes 4.
A lowering limit detector portion 38 includes the mount plate 35, the lowering detection switch 36, and the cam 37. Furthermore, a main rope elongation compensating apparatus according to Embodiment 4 includes the extension portion 7 and the lowering limit detector portion 38.
In a main rope elongation compensating apparatus of this kind, the elongation of the main ropes 4 is compensated for by the movable spacers 15 being moved to the non-contact position in a similar manner to Embodiment 1. Hence, the counterweight overtravel space is kept substantially uniform, but the counterweight 6 and the extension portion 7 descend gradually. Then, when the counterweight 6 and the extension portion 7 descend to a position where all of the movable spacers 15 have moved to the non-contact position, the lowering detection switch 36 is activated by the hooks 33, outputting a detection signal. The detection signal is sent to the monitoring center, for example, and a trimming operation is performed on the main ropes 4.
Consequently, in addition to initial elongation, age-related elongation of the main ropes 4 can also be adapted to easily for a long period.
Moreover, the main ropes may be normal wire ropes, or they may be belts.
Furthermore, an elevator apparatus using a 1:1 roping method is shown in the above examples, but the roping method is not limited to the 1:1 roping method and may be a 2:1 roping method, for example.
In addition, plate-shaped movable spacers are shown in the above examples, but the movable spacers are not limited to a particular shape, and they may also be block-shaped, for example.
Furthermore, it is possible to use this spacer system or a system related to it using discrete steps, to reduce the buffer height instead of the counter weight length. Such a solution might be required due to too little space underneath the counterweight to mount the movable spacer system.

Claims

An elevator apparatus comprising an elevator main rope elongation compensating apparatus, said elevator apparatus comprising:
a hoistway (1);

a car (5);

a counterweight (6);

a main rope (4) suspending said car (5) and said counterweight (6) inside said hoistway (1); and

a counterweight buffer (9) installed below said counterweight (6) inside said hoistway (1),

said elevator main rope elongation compensating apparatus compensating for changes in a distance between said counterweight (6) and said counterweight buffer (9) due to elongation of said main rope (4), wherein

an extension portion (7) is mounted to a lower portion of said counterweight (6) characterized in that said extension portion (7) has a movable spacer (15) movable between a contact position directly above said counterweight buffer (9) and a non-contact position outside a region directly above said counterweight buffer (9).
The elevator apparatus according to Claim 1, wherein said extension portion (7) further includes a guide member (14) for guiding movement of said movable spacer (15).
The elevator apparatus according to Claim 1, wherein a plurality of said movable spacers (15) are provided, a stopper (16) being disposed on at least one of said movable spacers (15) so as to project upward, such that a movable spacer (15) immediately above is prevented from moving to said non-contact position until said movable spacer (15) having said stopper (16) moves to said non-contact position.
The elevator apparatus according to Claim 1, wherein said extension portion (7) further includes a contact-position locking device (21) for locking said movable spacer (15) in said contact position.
The elevator apparatus according to Claim 4, wherein said extension portion (7) further includes a forcing means (22) for forcing said movable spacer (15) toward said non-contact position, said movable spacer (15) being moved to said non-contact position when a lock held by said contact-position locking device (21) is released.
The elevator apparatus according to Claim 5, further comprising a lock release device (27) for releasing said lock held by said contact-position locking device (21), said lock release device (27) being disposed on a stationary portion inside said hoistway (1) and engaging with said contact-position locking device (21) if said counterweight (6) is lowered due to said elongation of said main rope (4).
The elevator apparatus according to Claim 6, wherein said lock release device (27) engages with said contact-position locking device (21) and releases said lock held by said contact-position locking device (21) when said counterweight (6) rises after descending to a lowermost lowering position.
The elevator apparatus according to Claim 6, further comprising a lock release detector portion (28) for detecting release of said lock held by said contact-position locking device (21).
The elevator apparatus according to Claim 1, wherein a plurality of said movable spacers (15) are provided, further comprising a lowering limit detector portion (38) for detecting when said counterweight (6) and said extension portion (7) descend such that all of said movable spacers (15) move to said non-contact position.