Elevator

Abstract

To provide an elevator capable of reducing the extension of a main rope due to fluctuations in the load capacity of a car.SOLUTION: An elevator 10 is configured so that a main rope 12 (see Fig. 1) is stretched from a sheave 24a of a hoisting machine 24 through a first fixed pulley 20 to a car 16, and so that the ascending / descending speed of the car 16 is slower than the hoisting speed of the sheave 24a. It comprises: a pulley braking unit 20a that causes the first fixed pulley 20 to apply braking force; a hoisting braking unit 24b that causes the sheave 24a to apply braking force; and a control device 30 that controls the drive of the hoisting machine 24 and controls the pulley braking unit 20a and the hoisting braking unit 24b. The control device 30 causes both the sheave 24 and the first fixed pulley 20 to apply braking force via the hoisting braking unit 24b and the pulley braking unit 20a when stopping the car 16 within a landing zone.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to elevators, and more particularly to elevator main ropes. [Background technology]

[0002] A traction elevator is configured to raise and lower a car using a main rope stretched across a hoist. The car is then configured to land in a landing zone (landing area) that is preset for each floor landing using a landing position detection device. Here, the landing zone refers to the range of allowable vertical deviation (step) of the car floor relative to the height of the landing floor, and the car doors can be opened and closed only when the car lands within the landing zone.

[0003] On the other hand, the main rope may expand and contract due to fluctuations in the load on the car, and such expansion and contraction may cause the car's stopping position to shift vertically from the landing zone, resulting in a step between the landing floor surface and the car floor surface.

[0004] In this regard, Patent Document 1 discloses an elevator in which the vertical position of the car can be adjusted by moving a pair of car hoists mounted on the bottom surface of the car horizontally to change the distance between the two hoists, thereby eliminating the step between the car floor and the landing floor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-227133 Summary of the Invention [Problem to be solved by the invention]

[0006] The elevator described in Patent Document 1 above can eliminate the step between the landing floor and the car floor, but has the problem that it cannot reduce the elongation of the main rope due to fluctuations in the car's load.

[0007] An object of the present invention is to provide an elevator that can reduce the elongation of the main rope caused by fluctuations in the load of the elevator car. [Means for solving the problem]

[0008] The elevator of the present invention is an elevator in which a main rope is stretched from the sheave of the hoisting machine through a pulley to the car, and is configured so that the ascent and descent speed of the car is slower than the hoisting speed of the sheave.It is equipped with a pulley braking unit that applies a braking force to the pulley, a hoisting braking unit that applies the braking force of the sheave, and an operation control unit that controls the drive of the hoisting machine and also controls the pulley braking unit and the hoisting braking unit, and the operation control unit is configured to apply braking force to both the sheave and the pulley via the hoisting braking unit and the pulley braking unit when the car is to be stopped in a predetermined landing area.

[0009] In the elevator of the present invention, the operation control unit may have a first car position adjustment mode that adjusts the vertical position of the car by increasing the elongation of the main rope by releasing the braking state of the pulley braking unit.

[0010] In the elevator of the present invention, the operation control unit may have a second car position adjustment mode that adjusts the vertical position of the car by driving the hoist to release the braking state of the pulley braking unit while tension is applied to the main rope between the sheave and the pulley.

[0011] In the elevator of the present invention, the pulley braking unit may be configured to release the braking state when the braking force is equal to or greater than a predetermined value. [Effects of the Invention]

[0012] In the elevator of the present invention, braking forces act on both the sheave and the pulley, so frictional forces can be applied to the main rope via the sheave and the pulley, thereby reducing the elongation of the main rope extending from the sheave to the pulley. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram illustrating a schematic view of the overall configuration of an elevator according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing functional blocks centered around the control device shown in FIG. [Figure 3] FIG. 3 is a flowchart showing the flow of a control process for determining whether or not the car position adjustment mode can be executed. DETAILED DESCRIPTION OF THE INVENTION

[0014] An elevator 10 according to one embodiment of the present invention will be described below with reference to the drawings. In each drawing, the horizontal direction perpendicular to the axial direction of the sheave 24a of the hoisting machine 24 will be referred to as the horizontal direction X, and the vertical direction will be referred to as the vertical direction Y.

[0015] Fig. 1 is a diagram showing the overall configuration of an elevator 10. As shown in Fig. 1, the elevator 10 includes a car 16 and a counterweight 18 suspended so as to be vertically movable within a hoistway 14 via a steel main rope 12, a first fixed pulley (pulley) 20, a second fixed pulley 22, and a hoist 24. The first fixed pulley 20 and the second fixed pulley 22 are attached to support frames FL1 and FL2, respectively, which are installed near the ceiling of the hoistway 14.

[0016] In addition, in the elevator 10 of this embodiment, the main rope 12 is stretched so that the speed ratio (roping ratio) between the hoisting speed of the sheave 24a in the hoisting machine 24 and the lifting speed of the car 16 is 2:1. Specifically, one end of the main rope 12 is fixed via a hitch (fixing device) BL1 to a support frame FL3 provided near the ceiling of the elevator shaft 14, and the main rope 12 hangs down directly downward and spans a pair of under-car pulleys 16a, 16b provided at the bottom of the elevator car 16, a first fixed pulley 20 near the ceiling of the elevator shaft 14, a sheave 24a of a hoisting machine 24 fixed directly above a pit 14P in the elevator shaft 14, a second fixed pulley 22 near the ceiling of the elevator shaft 14, and a pulley 18a provided at the top of the counterweight 18, in this order, with the other end connected and fixed via a hitch (fixing device) BL2 to a support beam 15 installed near the ceiling of the elevator shaft 14. In this embodiment, the under-car pulleys 16a, 16b of the elevator car 16 function as movable pulleys.

[0017] In this embodiment, the hoisting machine 24 is positioned slightly above the pit 14P of the elevator shaft 14 as part of measures to prevent flooding during floods, etc., but it may also be positioned within the pit 14P or elsewhere within the elevator shaft 14.

[0018] In addition, a hoisting brake unit (see FIG. 2) 24b is provided on the hoisting machine 24. This hoisting brake unit 24b is a disc brake type braking mechanism, and has the function of stopping the rotation of the sheave 24a by applying a braking force.

[0019] The first fixed pulley 20 is also provided with a disc brake type pulley braking unit (see FIG. 2) 20a. The pulley braking unit 20a has the function of applying a braking force to the first fixed pulley 20 to stop the rotation of the first fixed pulley 20. In this embodiment, the main rope 12 is stretched over about half a circumference, in other words, about 160 degrees to about 180 degrees, between the first fixed pulley 20 and the sheave 24a, so that a sufficient braking force can be applied to the main rope 12 via the first fixed pulley 20 and the sheave 24a. The hoisting braking unit 24b and the pulley braking unit 20a may be drum type brake mechanisms.

[0020] It is also preferable to provide an overload protection device 20b on the first fixed pulley 20. This overload protection device 20b is a torque limiter that serves to limit the braking force that the pulley braking unit 20a applies to the first fixed pulley 20, in other words, the braking force that acts on the first fixed pulley 20 via the pulley braking unit 20a so that the torque does not exceed a predetermined value. This makes it possible to prevent excessive braking force from acting on the first fixed pulley 20.

[0021] As shown in Fig. 1, the car 16 is provided with a landing position detection device 16c that detects its vertical position. This landing position detection device 16c has the role of stopping the car 16 within a landing zone (landing area) by detecting position detection plates 14w that are installed on the wall surface of the elevator shaft 14 in correspondence with each floor landing. Here, the landing zone refers to the range of allowable vertical deviation (step) of the floor surface of the car 16 relative to the height of the landing floor surface, and the car door 17 of the car 16 can be opened and closed on the condition that the car 16 lands within the landing zone.

[0022] The elevator 10 also includes a control device 30 that controls the operation of the car 16. This control device 30 is installed on a wall or the like in the hoistway 14 so as not to interfere with the ascent and descent of the car 16 or the counterweight 18, and has the function of raising and lowering the car 16 based on call operations performed via a hall operating panel (not shown) or a car operating panel (not shown), as well as of controlling the overall operation of the car 16, such as controlling the open / closed state of the car doors 17.

[0023] FIG. 2 is a functional block diagram centered on the control device 30. As shown in FIG. 2, the control device 30 detects the vertical position of the car 16 via the landing position detection device 16c and controls the lifting and lowering of the car 16 so that the car 16 stops in a preset landing zone. At this time, the control device 30 applies a braking force to the sheave 24a via the hoisting brake unit 24b provided on the hoisting machine 24 and also applies a braking force via the pulley brake unit 20a provided on the first fixed pulley 20 (hereinafter referred to as "braking mode"). Even if the load on the car 16 fluctuates, friction (braking) force acts on the main rope 12 via both the sheave 24a and the first fixed pulley 20, so that the tension on the main rope 12 located between the sheave 24a and the first fixed pulley 20 can be alleviated.

[0024] As a result, it is possible to suppress elongation of the main rope 12 between the sheave 24a and the first fixed pulley 20. Furthermore, when driving the hoisting machine 24 to rotate the sheave 24a, the control device 30 releases the braking state of the hoisting brake unit 24b and the pulley brake unit 20a before or at the same time as driving the hoisting machine 24. This allows the car 16 to smoothly rise and fall toward the landing of the destination floor.

[0025] Furthermore, it is preferable that the control device 30 executes a car position adjustment mode in which the stopping position of the car 16 is adjusted when the stopping position of the car 16 deviates from a preset landing zone. More specifically, the control device 30 executes a first car position adjustment mode when the stopping position of the car 16 is shifted above the preset landing zone. The first car position adjustment mode is a mode in which only the braking of the pulley braking unit 20a is released during execution of the above-mentioned braking mode to set the car in a non-braking state.

[0026] As a result, the braking force via the pulley braking part 20a no longer acts on the main rope 12, so the tension acting on the main rope 12 between the sheave 24a and the first fixed pulley 20 increases slightly, and the elongation of the main rope 12 increases in proportion to the increase in tension. This makes it possible to lower the stopping position of the car 16 downward.

[0027] On the other hand, the control device 30 executes a second car position adjustment mode when the stopping position of the car 16 is shifted below a preset landing zone. Here, the second car position adjustment mode is a mode including a first adjustment step, which will be described later, and a second adjustment step that is performed after the first adjustment step. In the first adjustment step, the control device 30 releases only the braking force of the hoisting brake unit 24b while executing the braking mode, and then drives the hoisting machine 24 to slightly rotate the sheave 24a in the rotation direction α (see FIG. 1), i.e., in the direction that raises the car 16.

[0028] At this time, a braking force is applied to the first fixed pulley 20 via the pulley braking portion 20a. Therefore, as the sheave 24a rotates, the tension of the main rope 12 between the sheave 24a and the first fixed pulley 20 is increased and maintained.

[0029] In the second adjustment step, the control device 30 releases the braked state of the pulley braking unit 20a. As a result, the main ropes 12 contract, and the car 16 moves upward by a distance equivalent to half the contracted distance of the main ropes 12.

[0030] In this embodiment, the control device 30 may temporarily execute the second car position adjustment mode described above while the braking mode is being executed, thereby moving the landing position of the car 16 upward. As a result, the braking mode is executed again after the adjustment of the vertical position of the car 16 in the second car position adjustment mode is completed.

[0031] FIG. 3 is a flowchart showing the flow of control processing in the control device 30 for determining whether or not the car position adjustment mode can be executed.

[0032] 3, when the control device 30 detects via the landing position detection device 16c that the car 16 has stopped at the landing hall (step S1: YES), it executes the braking mode (step S2), which causes a braking force to act on the sheave 24a and the first fixed pulley 20 via the hoisting braking unit 24b and the pulley braking unit 20a.

[0033] The control device 30 determines whether the stopping (landing) position of the car 16 is within a preset landing zone (step S3). If the stopping position of the car 16 deviates from the preset landing zone (step S3: NO), the control device 30 determines whether the floor surface of the car 16 is shifted upward from the preset landing zone (step S4). If the car 16 is shifted upward from the landing zone (step S4: YES), the control device 30 executes a first car position adjustment mode (step S5). This allows the landing position of the car 16 to be corrected so that it is within the preset landing zone.

[0034] On the other hand, if the car 16 is deviated downward from the landing zone, the control device 30 executes the second car position adjustment mode (step S4: NO, step S6). This increases the tension acting on the main rope 12 between the sheave 24a and the first fixed pulley 20, and the main rope 12 contracts as the braking state of the pulley braking unit 20a is released, thereby correcting the landing position of the car 16 to be in the preset landing zone.

[0035] According to the elevator 10 of this embodiment, a braking force acts on both the sheave 24a and the first fixed pulley 20. Therefore, a frictional force can be applied to the main rope 12 via the sheave 24a and the first fixed pulley 20. This makes it possible to reduce the elongation of the main rope 12 from the sheave 24a to the first fixed pulley 20 (which can also be expressed as the expansion and contraction of the main rope 12).

[0036] As a result, it is possible to prevent the landing position of the car 16 from deviating from a preset landing zone due to elongation of the main rope 12.

[0037] In the above embodiment, an example is described in which, during execution of the braking mode as the first car position adjustment mode, only the braked state of the pulley brake unit 20a is released and braking force is applied only to the hoist brake unit 24b, thereby increasing the elongation of the main rope 12 and lowering the stop position of the car 16. However, the present invention is not limited to this. For example, if it is expected that the stop position of the car 16 will drop too far downward, the first car position adjustment mode may be a mode in which, during execution of the braking mode, only the brake of the hoist brake unit 24b is released and braking force is applied only to the pulley brake unit 20a, while the sheave 24a is held in a state where it is slightly rotated in the rotation direction α via the hoist 24. Here, the distance by which the sheave 24a is rotated in the rotation direction α may be set to be shorter than the distance by which the sheave 24a is rotated in the rotation direction α in the second car position adjustment mode described above.

[0038] This increases the tension acting on the main rope 12 between the first fixed pulley 20 and the sheave 24a, making it possible to shorten the distance by which the stopping position of the car 16 drops downward when the braked state of the pulley braking unit 20a is released. This makes it possible to adjust the stopping position of the car 16 so that it does not drop too far downward.

[0039] In the above embodiment, an example is given in which the main ropes 12 are stretched so that the speed ratio between the hoisting speed of the sheave 24a in the hoisting machine 24 and the lifting / lowering speed of the car 16 is 2:1, but the present invention is not limited to this. For example, the main ropes 12 may be stretched so that the speed ratio between the hoisting speed of the sheave 24a and the lifting / lowering speed of the car 16 is 4:1.

[0040] In the above embodiment, the first car position adjustment mode or the second car position adjustment mode is executed when the stopping position of the car 16 deviates from the landing zone. However, the present invention is not limited to this. For example, the car position adjustment mode may be executed when the stopping position of the car 16 is within the landing zone but deviates vertically from a preset reference landing position. Here, the reference landing position is set to, for example, a position where the vertical position of the floor surface of the car 16 coincides with the vertical position of the landing floor surface. More specifically, when the stopping position of the car 16 is within the landing zone, the control device 30 may execute the first car position adjustment mode when the stopping position of the car 16 is deviated above the reference landing position, and may execute the second car position adjustment mode when the stopping position of the car 16 is deviated below the reference landing position.

[0041] In this case, it is also possible that the car door 17 is in an open state because the stopping position of the car 16 is within the landing zone, but in such a case, it is preferable to temporarily close the car door 17 via the control device 30 to put it in a closed state, and then execute the first car position adjustment mode or the second car position adjustment mode.

[0042] In addition, instead of closing the car door 17, an announcement or a warning sound indicating that the above-mentioned car position adjustment mode will be executed may be made via a speaker (not shown) provided on the hall operating panel (not shown) or the car operating panel (not shown), and then the first car position adjustment mode or the second car position adjustment mode may be executed.

[0043] The present invention can be implemented in various forms, including improvements, modifications, and variations based on the knowledge of those skilled in the art, without departing from the spirit of the invention. Furthermore, the invention can be implemented in a form in which any of the features of the invention are replaced with other technology, as long as the same action or effect is achieved. [Explanation of symbols]

[0044] 10 Elevator 12 Main rope 14 Elevator shaft 16 Car 16a, 16b Under-cage pulley 16c Implantation position detection device 18 Counterweight 18a Pulley 20 1st fixed pulley (pulley) 20a Pulley brake part 20b Overload protection device 22 Second fixed pulley 24 Hoisting machine 24a sheave 24b Hoisting brake part 30 Control device S1~S6 steps X Horizontal Y vertical direction α Rotation direction

Claims

1. An elevator in which a main rope is laid from a sheave of a hoisting machine to a car via a pulley, and the lifting speed of the car is slower than the hoisting speed of the sheave, a pulley braking unit that applies a braking force to the pulley; a hoisting braking unit that applies a braking force to the sheave; an operation control unit that controls the driving of the hoisting machine and controls the pulley braking unit and the hoisting braking unit; Equipped with The operation control unit is configured to apply a braking force to both the sheave and the pulley via the hoisting braking unit and the pulley braking unit when stopping the car in a preset landing area. Elevator.

2. The operation control unit has a first car position adjustment mode in which the vertical position of the car is adjusted by increasing the elongation of the main rope by releasing the braking state of the pulley braking unit.

2. The elevator of claim 1.

3. The operation control unit has a second car position adjustment mode in which the vertical position of the car is adjusted by driving the hoist to release the braking state by the pulley braking unit while tension is applied to the main rope between the sheave and the pulley.

2. The elevator of claim 1.

4. The pulley braking unit is configured to release the braking state when the braking force is equal to or greater than a predetermined value. An elevator according to any one of claims 1 to 3.

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