EP1598300A1

EP1598300A1 - Governor for elevator, and elevator equipment

Info

Publication number: EP1598300A1
Application number: EP03700485A
Authority: EP
Inventors: Mineo c/o Mitsubishi Denki Kabushiki K. OKADA
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2003-01-08
Filing date: 2003-01-08
Publication date: 2005-11-23
Also published as: CN100335395C; WO2004063074A1; JPWO2004063074A1; KR20050002815A; KR100685556B1; JP4209393B2; CN1639043A; EP1598300A4

Abstract

In an elevator speed governor, a reset assisting mechanism for assisting in an operation for resetting a speed governor main body is disposed on the speed governor main body. The reset assisting mechanism includes an externally-operated acting lever. An operating member for pressing and operating the acting lever is disposed on an upper portion of a car. When maintenance personnel cannot climb in onto the car, the acting lever can be pressed and operated by the operating member to assist in the operation for resetting the speed governor main body.

Description

TECHNICAL FIELD

The present invention relates to an elevator speed governor installed inside a hoistway for detecting overspeed of a car and to an elevator apparatus using that speed governor.

BACKGROUND ART

In conventional elevator apparatuses, if a speed of a car reaches a preset overspeed, emergency stopping apparatuses mounted to the car are activated by a speed governor to make the car perform an emergency stop.
In a resetting operation after an emergency stop, a braked state of the emergency stopping apparatuses is released, then the resetting operation is performed on the speed governor. In elevator apparatuses in which the speed governor is disposed in an upper portion inside a hoistway instead of in a machine room, maintenance personnel must open landing doors from a landing on an uppermost floor, climb on top of the car, and reach for the speed governor from on top of the car to perform the resetting operation.
However, if the emergency stop position of the car is in a vicinity of the landing on the uppermost floor, it may not be possible transfer to the roof of the car even if the landing doors are opened. In that case, it is possible to raise the car to release the braked state of the emergency stopping apparatuses on car guide rails, but it is not possible to lower the car so that the maintenance personnel can climb onto the car.
In regard to this, it is conceivable that a resetting opening could be disposed in a wall portion of the landing on the uppermost floor, for example, for maintenance personnel to perform the resetting operation on the speed governor by inserting a hand through this resetting opening into the hoistway.
However, in order to provide the resetting opening, construction work is required to open an aperture in the wall portion, making extra work and also lowering fire-resistance and design properties. Furthermore, since the resetting opening must be positioned significantly higher than the landing door, and the speed governor is also positioned far back from the resetting opening, a resetting operation through a resetting opening is difficult.

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 speed governor enabling a resetting operation to be performed easily even if an emergency stop position of a car is in a vicinity of a landing on an uppermost floor, and to provide an elevator apparatus using that speed governor.
In order to achieve the above object, according to one aspect of the present invention, there is provided an elevator speed governor including: a speed governor main body disposed in an upper portion inside a hoistway, for detecting when a speed of a car reaches a preset overspeed and operating to activate an emergency stopping apparatus mounted to the car; a reset assisting mechanism disposed on the speed governor main body and having an externally-operated acting lever, the acting lever being operated to assist in an operation for resetting the speed governor main body; and an operating member disposed on an upper portion of the car, for pressing and operating the acting lever.
According to another aspect of the present invention, there is provided an elevator apparatus including: a car that is raised and lowered inside a hoistway; an emergency stopping apparatus mounted to the car, for making the car perform an emergency stop; a speed governor main body disposed in an upper portion inside the hoistway, for detecting when a speed of the car reaches a preset overspeed and operating to activate the emergency stopping apparatus; a reset assisting mechanism disposed on the speed governor main body and having an externally-operated acting lever, the acting lever being operated to assist in an operation for resetting the speed governor main body; and an operating member disposed on an upper portion of the car, for pressing and operating the acting lever.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a structural diagram showing an elevator apparatus according to an example of a preferred embodiment of the present invention;
Figure 2 is a front elevation showing a speed governor main body from Figure 1;
Figure 3 is a front elevation showing part of Figure 2; and
Figure 4 is a front elevation showing a state in which a resetting lever from Figure 3 is swung to a reset position.

BEST MODE FOR CARRYING OUT THE INVENTION

A preferred embodiment of the present invention will now be explained with reference to the drawings.
Figure 1 is a structural diagram showing an elevator apparatus according to an example of a preferred embodiment of the present invention. In the figure, a driving machine 2 is installed in an upper portion inside the hoistway 1. A main rope 3 is wound onto a drive sheave 2a of the driving machine 2. A car 4 is suspended by a first end portion of the main rope 3, and a counterweight 5 is suspended by a second end portion of the main rope 3. A pair of car guide rails 6 and a pair of counterweight guide rails (not shown) for guiding raising and lowering of the car 4 and the counterweight 5 are installed inside the hoistway 1.
An emergency stopping apparatus 7 for making the car 4 perform an emergency stop is mounted to a lower portion of the car 4. A speed governor supporting member 8 is secured in a vicinity of an upper end portion of the car guide rails 6. A speed governor main body 9 for detecting overspeed of the car 6 and activating the emergency stopping apparatus 7 is supported on this speed governor supporting member 8.
A rotatable tension sheave 10 is disposed in a vicinity of a bottom portion of the hoistway 1. A loop-shaped speed governor rope 11 is wound around the speed governor main body 9 and the tension sheave 10. The speed governor rope 11 is connected to the emergency stopping apparatus 7 by means of a lever 12, and is moved cyclically together with the raising and lowering of the car 4.
A landing door 14 is disposed on a landing 13. A bar-shaped operating member (operating cam) 75 is secured to an upper portion of the car 4 so as to stand upright. The operating member 75 is disposed so as to be brought into close proximity with the speed governor main body 9 if the car 4 moves above the landing 13 on the uppermost floor.
Figure 2 is a front elevation showing the speed governor main body 9 from Figure 1. In the figure, a sheave 21 around which the speed governor rope 11 is wound is supported by a base 23 so as to be rotatable around a sheave shaft 22. A pair of first and second flyweights 25 that are pivotable around first and second pins 24 aremountedto side surfaces of the sheave 21. This pair of flyweights 25 are linked to each other by a link 26.
A moving pawl 37 is secured to a first end portion of the first flyweight 25. The first flyweight 25 is pivoted by centrifugal force due to the rotation of the sheave 21. Thus, the moving pawl 37 is displaced radially outwards relative to the sheave 21. A balancing spring 27 opposing the centrifugal force is disposed between a second end portion of the first flyweight 25 and the sheave 21. A car-stopping switch 28 for activating a braking apparatus (not shown) of the driving machine 2 is mounted to the base 23. The car-stopping switch 28 has a switching lever 28a that is operated by the moving pawl 37.
A trip lever 72 that is pivotable around a shaft 71 that is parallel to the first pin 24 is mounted to the sheave 23. A portion of the trip lever 72 is placed in contact with the first flyweight 25, and is pivoted around the shaft 71 by the pivoting of the first flyweight 25. A torsion spring 73 for applying force in a direction that places the trip lever 72 in contact with the first flyweight 25 (clockwise in the figure) is disposed on the shaft 71.
A ratchet 30 that is rotatable around the sheave shaft 22 is disposed on the base 23. A large number of teeth are disposed on an outer peripheral portion of this ratchet 30. A pawl 29 that selectively engages with either the trip lever 72 or the ratchet 30 is pivotably supported by the first pin 24. The pawl 29 is forced by a retracting spring 74 in such a direction as to engage the ratchet 30. The pawl 29 is normally engaged with the trip lever 72, and separated from the ratchet 30, but when disengaged from the trip lever 72, the pawl 29 is pivoted by the force of the retracting spring 74 and engages with the teeth of the ratchet 30.
A shoe 32 that is pressed against the speed governor rope 11 is pivotably mounted to an arm 31 pivotably mounted to the base 23. A spring shaft 33 is passed through a spring bearing portion 31a of the arm 31. A connecting lever 34 is connected between a first end portion of the spring shaft 33 and the ratchet 30. A spring bearing member 35 is disposed on a second end portion of the spring shaft 33. A rope gripping spring 36 for pressing the shoe 32 against the speed governor rope 11 is disposed between the spring bearing portion 31a and the spring bearing member 35.
A resetting lever 42 is mounted to the base 23. The resetting lever 42 is swingable around a shaft 43 that is parallel to the sheave shaft 22. A rotatable lug 44 that is pressed by the swinging of the resetting lever 42 is disposed on the pawl 29. A return spring 45 for forcing the resetting lever 42 in such a direction as to separate from the lug 44 is disposed between the base 23 and the resetting lever 42.
An acting lever 76 that is operated externally so as to be pivoted together with the resetting lever 42 around the shaft 43 is mounted to the shaft 43. A reset assisting mechanism in this embodiment includes: the resetting lever 42; the shaft 43; the lug 44; the return spring 45; and the acting lever 76. This reset assisting mechanism allows the acting lever 76 to be operated to reset a portion of the mechanism of the speed governor main body 9, specifically the pawl 29 and the trip lever 72, from an active state due to overspeed detection to the state before activation. In other words, the reset assisting mechanism assists an operation for resetting the speed governor main body 9.
The elevator speed governor in this embodiment includes: the speed governor main body 9; the reset assisting mechanism; and the operating member 75.
Figure 3 is a front elevation showing part of Figure 2, and Figure 4 is a front elevation showing a state in which the resetting lever 42 from Figure 3 is swung to a reset position. In Figure 3, the resetting lever 42 is in a normal position, and is separated from the lug 44. From the state in Figure 3, if the operating member 75 is displaced upward, the acting lever 73 is pressed by the operating member 75 and pivoted, and the resetting lever 42 is also swung to the reset position in opposition to the return spring 45. Thus, the lug 44 is pressed by the resetting lever 42, and the pawl 29 is pivoted clockwise in the figure in opposition to the retracting spring 74, and engages with the trip lever 72.
Next, operation will be explained. If the elevating speed of the car 4 reaches a first overspeed (normally around 1.3 times a rated velocity), the moving pawl 37 is placed in contact with the switch lever 28a of the car-stopping switch 28 by pivoting of the flyweights 25 due to centrifugal force, pivoting the switch lever 28a. Thus, the switch 28 is activated, interrupting the power source of the driving machine 2, and the car is stopped by the braking apparatus of the driving machine 2.
If the main rope 3 breaks, for example, and the car 4 continues to descent without stopping, even though the driving machine 2 has stopped, when the descent speed of the car 4 reaches a second overspeed (normally around 1.4 times the rated velocity), the flyweights 25 pivot further, and the amount of pivoting of the trip lever 72 also increases together therewith, dislodging engagement between the trip lever 72 and the pawl 29. In this manner, the pawl 29 is pivoted by the force of the retracting spring 74 and engages with the teeth of the ratchet 30. Thus, the ratchet 30 is rotated counterclockwise in Figure 2 together with the sheave 21.
Due to this rotation of the ratchet 30, the arm 31 is pivoted counterclockwise in Figure 2, the shoe 32 is placed in contact with the speed governor rope 11, and the shoe 32 is pressed against the speed governor rope 11 by the rope gripping spring 36, braking the speed governor rope 11. When cycling of the speed governor rope 11 is stopped, the lever 12 is actuated by the car 4 as it continues to descend, activating the emergency stopping apparatuses 7.
Next, a resetting operation after activation of the emergency stopping apparatuses 7 and the speed governor main body 9 will be explained. In the resetting operation, first the car 4 is raised slightly to release the braked state of the emergency stopping apparatus 7 on the car guide rails 6. Then, when the car 4 is raised further, the sheave 21 is pivoted in a clockwise direction in Figure 2 by means of the speed governor rope 3, disengaging the pawl 29 and the ratchet 30, and the ratchet 30 also pivots clockwise in the figure, returning to its original position. Thus, the arm 31 returns to its original position, and the shoe 32 separates from the speed governor rope 11.
After this, the car 4 is raised to a position from which it is possible to climb in onto the roof of the car 4 from the landing 13 of the uppermost floor, then the landing door 14 of the landing 13 of the uppermost floor is opened, and maintenance personnel climb onto the car 4. Then, the resetting operation is completed by reaching for the speed governor main body 9 from on top of the car 4, and engaging the pawl 29 in the trip lever 72.
Thus, if the maintenance personnel can climb onto the car 4, the pawl 29 can be engaged in the trip lever 72 manually, and it is not necessary to use the reset assisting mechanism.
On the other hand, if the position of the car 4 when the speed governor main body 9 performs the second overspeed operation is in the vicinity of the landing 13 of the uppermost floor, and it is not possible to open the landing door 14 and climb in onto the roof of the car 4 from that position, the car 4 is raised further, and the acting lever 76 is pressed using the operating member 75. Thus, on the speed governor main body 9, the resetting lever 42 is pivoted in a clockwise direction in Figures 2 to 4 in opposition to the return spring 45, and the lug 44 is pressed by the resetting lever 42. Thus, the pawl 29 is pivoted in a clockwise direction in Figures 2 to 4 in opposition to the retracting spring 73, and engages with the trip lever 72.
Moreover, if the resetting lever 42 and the lug 44 are not in a positional relationship facing each other, the car 4 is simply raised for a while in that state to rotate the sheave 21 in a clockwise direction. Thus, the operating member 75 continues to be placed in contact with the acting lever 76, and the lug 44, which rotates together with the sheave 21, is placed in contact with the resetting lever 42 in the reset position and pressed.
By operating in this manner, even if the car 4 is in the vicinity of the landing 13 on the uppermost floor and it is not possible to open the landing door 14 and climb in onto the roof of the car 4 from that position, the pawl 29 can be engaged in the trip lever 72 by remote control from the landing 13.
Consequently, even if the speed governor main body 9 is disposed inside the hoistway 1, the resetting operation can be performed on the speed governor main body 9 easily from a remote location without having to dispose an opening for accessing the speed governor main body 9 in the landing wall, thereby enabling workability of the resetting operation to be improved.
Furthermore, it is also no longer necessary to lay wires, etc., for remote control from the speed governor main body 9 to the landing 13, enabling reductions in the degree of freedom of the equipment layout inside the hoistway 1 to be prevented.
Moreover, even if the emergency stopping apparatus 7 is activated below the uppermost floor, it is possible to use the operating member 75 to perform the resetting operation without the maintenance personnel having to climb in on top of the car 4. However, because complicated procedures such as releasing the safety apparatus, for example, may be required in order to move the car 4 above the landing position of the uppermost floor, it is often simpler to climb in on top of the car 4 as described above.
In the above example, the operating member 75 is fixed on top of the car 4, but the operating member may also be made vertically movable relative to the car 4. In that case, the resetting operation can be performed using the operating member without having to move the car 4 above the landing position of the uppermost floor. Furthermore, if the operating member is made vertically movable, it may be raised and lowered manually from inside the cabin, or it may also be raised and lowered by a driving force such as from an electric motor, etc.
In addition, in the above example, a "machine-roomless" elevator is described, but the present invention can also be applied to elevator apparatuses having a machine room provided that the speed governor is disposed in an upper portion inside the hoistway.

Claims

An elevator speed governor comprising:

a speed governor main body disposed in an upper portion inside a hoistway, for detecting when a speed of a car reaches a preset overspeed and operating to activate an emergency stopping apparatus mounted to said car;

a reset assisting mechanism disposed on said speed governor main body and having an externally-operated acting lever, said acting lever being operated to assist in an operation for resetting said speed governor main body; and

an operating member disposed on an upper portion of said car, for pressing and operating said acting lever.
The elevator speed governor according to Claim 1, wherein:

said speed governor main body further comprises:

a sheave around which a speed governor rope for activating said emergency stopping apparatus is wound, rotation of said sheave corresponding to said speed of said car;

a pawl pivotably disposed on said sheave;

a flyweight pivotably disposed on said sheave, said flyweight being pivoted by centrifugal force due to said rotation of said sheave;

a trip lever pivotably disposed on said sheave and normally engaged with said pawl, said trip lever being disengaged from said pawl when said speed of said car reaches said overspeed by being pivoted by said pivoting of said flyweight; and

a shoe for braking said speed governor rope when said trip lever and said pawl disengage, and

said reset assisting mechanism further comprises:

a resetting lever that is displaceable between a normal position and a reset position, said acting lever being pressed and operated to displace said resetting lever from said normal position to said reset position to engage said pawl in said trip lever.
The elevator speed governor according to Claim 1, wherein said operating member is vertically movable relative to said car.
An elevator apparatus comprising:

a car that is raised and lowered inside a hoistway;

an emergency stopping apparatus mounted to said car, for making said car perform an emergency stop;

a speed governor main body disposed in an upper portion inside said hoistway, for detecting when a speed of said car reaches a preset overspeed and operating to activate said emergency stopping apparatus;

a reset assisting mechanism disposed on said speed governor main body and having an externally-operated acting lever, said acting lever being operated to assist in an operation for resetting said speed governor main body; and

an operating member disposed on an upper portion of said car, for pressing and operating said acting lever.
The elevator apparatus according to Claim 4, wherein said operating member is secured to an upper portion of said car such that said operating member presses and operates said acting lever when said car is moved above a landing position of an uppermost floor.