WO2011021064A1

WO2011021064A1 - Elevator apparatus

Info

Publication number: WO2011021064A1
Application number: PCT/IB2009/007673
Authority: WO
Inventors: Mitsuru Kato
Original assignee: Otis Elevator Co
Current assignee: Otis Elevator Co
Priority date: 2009-08-19
Filing date: 2009-12-09
Publication date: 2011-02-24
Anticipated expiration: 2012-02-19
Also published as: JP2011042411A; JP5390988B2

Abstract

The present invention provides an elevator for suppressing the oscillation of the car when passengers get on and off. A car brake (19) is attached to a car (8) of a so-called traction type elevator apparatus. Brake shoes (24) of the car brake (19) are connected to the car (8) via brake arms (22) with dampers (30) and contact car guide rails (12), generating a braking force. In addition, the car brake (19) is operated when the car (8) arrives at a floor, so that the oscillation of the car (8), which is moved vertically by passengers getting on and off, is suppressed by the dampers (30) and operation of the car (8) beyond an expansion and contraction range of two brake arms (22) is prevented.

Description

DESCRIPTION

ELEVATOR APPARATUS

Technical Field

The present invention pertains to an elevator apparatus. In particular, the present invention pertains to an elevator apparatus in which a car includes a brake.

Background Art

In a so-called traction type elevator apparatus, a car and a

counterweight are suspended on a main rope passing over the drive sheave of a hoist, and the car is raised and lowered by rotationally driving said drive sheave. When the car arrives at a floor, the drive sheave is braked by a hoist brake. In this elevator apparatus, however, when passengers or baggage were loaded and unloaded from the car upon arrival at a designated floor and the car live load changed, the car may oscillate vertically according to the expansion and contraction of the main rope on which the car was suspended.

Accordingly, for example, as in an invention described in, Japanese Unexamined Patent Application Publication 11-124281, an elevator apparatus in which a car brake is attached to a car has been proposed. In the car brake described in this reference, a pair of levers, which pivot freely, are oppositely arranged bracketing the car guide rails guiding the ascent and descent of the car, and by inserting the car guide rails between the ends of these two levers, braking force can be applied to the car.

In addition, when the car arrives at a floor, the car brake is operated in addition to braking by the hoist brake to apply a braking force to the car when it is raised and lowered according to the expansion and contraction of the main rope, thereby attenuating the car oscillation.

Disclosure of Invention

Technical Problem

In the technique described in this reference, the braking force of the car brake is set weakly to the extent that movement of the car is still allowable. Accordingly, both levers of the above-mentioned car brake, which ascend and descend along with the car, slide along the above-mentioned car guide rails to attenuate the oscillation of the car.

Technical Solution

The present invention provides an elevator apparatus in which the comfort of riding is improved and which prevents oscillation of a car when passengers or baggage enter or leave.

The invention of Claim 1 is characterized by a brake assembly for an elevator car in an elevator apparatus, wherein the car is suspended from a main rope guided by a fixed member attached to the peripheral wall of a hoistway, the brake assembly comprising: a braking member that contacts the fixed member so that the car can be moved relative to the braking member within a prescribed allowable range in the ascending and descending direction of the car, and an attenuator that attenuates oscillation of the car.

Brief Description of Drawings

Figure 1 shows the outline of the elevator apparatus as one possible embodiment of the present invention

Figure 2 is a side view showing details of a car. Figure 3 is a front view showing details of a car brake.

Figure 4 is a plan view showing details of the car brake.

Figure 5 is a flow chart showing control processing by an elevator controller.

Figure 6 is an illustrative diagram showing the operation of the car brake from the arrival of the car at a prescribed destination floor to starting its travel.

Figure 7 is a graph showing the displacement of the car due to the change of the live load. In the figure, (a) is a graph showing the displacement of the car in a comparative example, and (b) is a graph showing the

displacement of the car in an embodiment of the present invention.

Explanation of Reference

1 hoist

2 main rope

7 hoist brake

8 car

12 car guide rail (fixed member)

19 car brake

24 brake shoe (braking member)

24a brake shoe contact surfaces

30 damper (attenuator)

Best Mode for Carrying Out the Invention

Figures 1-7 show one possible embodiment of the present invention.

Among these, Figure 1 shows the outline of the elevator apparatus as a possible embodiment of the present invention. The elevator apparatus shown in Figure 1 is a so-called traction type. A hoist 1 of said elevator apparatus is equipped with a drive sheave 3 and a deflection sheave 4 over which a main rope 2 runs, a driving shaft 5 that rotates integrally with the drive sheave 3, a hoist motor 6 for rotationally driving the driving shaft 5, and a hoist brake 7 for braking the driving shaft 5. In addition, as is well known, a car 8 is suspended from one end of the main rope 2, whereas a counterweight 9 is suspended from the other end of the main rope 2. In a state in which the hoist brake 7 is released, an elevator controller 10 causes the rotational drive of the hoist motor 6, raising and lowering the car 8 in a hoistway 11.

The hoist brake 7 can be a so-called electromagnetic brake and generates braking force by press-contacting a brake shoe 7b against a brake drum 7a that rotates integrally with the driving shaft 5. In other words, when the car 8 stops, the brake shoe 7b is pressed against the brake drum 7a by a brake spring 7c. On the other hand, when the car 8 travels, the brake shoe 7b is pulled away from the brake drum 7a by an electromagnetic force generated by electrification of brake coils 7d.

Additionally, a pair of car guide rails 12 extending vertically are installed as fixed members in the hoistway 11. These car guide rails 12 can be formed with approximately T-shaped cross section from a steel material that is a magnetic material, and the rails are arranged opposite each other with a prescribed separation in the width direction of the hoistway 11. More specifically, the car guide rails 12, as shown in Figure 4 in addition to Figure 1, have a base part 12a fixed to a peripheral wall 11a of the hoistway 11 via several rail brackets 13, and a guide part 12b projecting from the approximate center in the width direction of the base part 12a. A guide shoe, not shown in the figure, installed in the car 8 is coupled with the guide part 12b of the car guide rails 12, guiding the car 8 along the car guide rails 12. Moreover, as shown in Figure 1, car position detectors 14 for detecting the height position of the car 8 are installed in the hoistway 11. The car position detector 14 detects the misalignment of a floor surface position of the car 8 from the floor surface position of a landing, not shown in the figure, when the car 8 arrives at a floor, and sends information about the amount of misalignment to the elevator controller 10. Furthermore, a car position detector 14 is installed for each service floor of the elevator apparatus, although this is not shown in the figure.

Figure 2 is a side view showing details of the car 8. As shown in Figure 2 in addition to Figure 1, the car 8 can be constituted with a car frame 15 with an approximately rectangular shape in a front view, and a car compartment 16 with an approximately parallelepiped shape that is installed inside the car frame 15. The door opening and closing type of a doorway 16a in the car compartment 16 is a so-called two-leaf double-slide door type and is opened and closed by a pair of sliding doors 17, 17. In addition, a door operator 18 for opening and closing these sliding doors 17, 17 is installed in the car 8, and the door operator 18 opens and closes the doorway 16a of the car compartment 16 based on instructions from the elevator controller 10.

The car frame 15 can be equipped with a pair of left and right vertical stiles 15a extending in the vertical direction, a bolster 15b for connecting the lower ends of these two vertical stiles 15a, and a crosshead 15c for connecting the upper ends of these vertical stiles 15a. In this embodiment, car brakes 19 are respectively installed at either ends in the longitudinal direction of the crosshead 15c. The brakes 19 could be installed at other suitable locations on the car 8.

Figures 3 and 4 are enlarged diagrams showing details of one embodiment of the car brake 19. Here, Figure 3 is a front view showing the car brake 19, and Figure 4 is a plan view showing the car brake 19. In addition, Figures 3 and 4 show operating states of the car brake 19.

As shown in Figures 3 and 4, the car brake 19 is equipped with a base plate 20 fixed to the upper surface of the crosshead 15c, a pair of brake arms 22 extending upward from the base plate 20, a pair of brake shoes 24 as braking members respectively mounted on these two brake arms 22, and an

electromotive cylinder 26 as an actuator for opening and closing the two brake arms 22. Moreover, a guide part 12b of the car guide rails 12 is inserted between two shoes, and the guide part 12b of the car guide rails 12 is sandwiched between the two brake shoes 24 to brake the car 8. Furthermore, the two brake arms 22 are biased in the directions separating them from each other by a pair of return springs 27 arranged obliquely to respectively connect said two brake arms 22 and base plate 20. In addition, a notch 20a into which the guide part 12b of the car guide rails 12 is inserted is formed in the base plate 20.

The two brake arms 22 are respectively equipped with piston rods 28, which are connected to the base plate 20 by pins 21 and can be swung in the rotational direction around the pins 21, and cylinder members 29 having cylinder bodies 29a in which a prescribed viscous fluid is sealed. Damper 30 of the so-called double-acting type that exerts a damping force in both extension operation and contraction operation is constituted by inserting piston 28a provided at the upper end of piston rods 28 into the cylinder main body 29 of cylinder member 29. Moreover, spring sheets 31, 32 are respectively mounted on the cylinder members.29 and the piston rods 28, and coil springs 33 are interposed between these two spring sheets 31, 32.

The cylinder members 29 of the two brake arms 22 have rods 29b extending upward from the cylinder bodies 29a, and brackets 29c projecting toward the car guide rails 12 are formed in the intermediate part in the longitudinal direction of the rods 29b. Furthermore, brake shoes 24 are respectively mounted at the tips of the brackets 29c on these two brake arms 22.

In addition, both longitudinal ends of the electromotive cylinder 26 are connected to the upper ends of the rods 29b of two cylinder members 29 by pins 25 so that these can be swung. Moreover, the elevator controller 10 rotationally drives a motor 26a of the electromotive cylinder 26 so that the electromotive cylinder 26 is expanded and contracted by a ball screw mechanism not shown in the figure, thereby swinging two brake arms 22 in the approaching and separating directions.

The two brake shoes 24 are constituted around a shoe body 34 having an approximately tabular shape, and connecting parts 34a projecting from the back surface of the shoe body 34 are connected to the bracket 29c of brake arms 22 by pins 23 so that they can be swung. Furthermore, brake linings 35 having contact surfaces 24a, which contact the car guide rails 12 when the car brake 19 is operated, are mounted on the front of the shoe body 34. These brake linings 35 have an approximately tabular shape formed of a permanently magnetic material, and buffer plates 36 made of a rubber are interposed between said brake linings 35 and the shoe body 34.

Therefore, the two brake arms 22 in the car brake 19 with the above constitution are swung toward each other by the electromotive cylinder 26, and while the guide part 12b of the car guide rails 12 is sandwiched between the two brake shoes 24, the brake linings 35 of these two brake shoes 24 are attracted to the guide part 12b of the car guide rails 12, generating a braking force. On the other hand, if the electromotive cylinder 26 is expanded to release the car brake 19, the two brake shoes 24 are pulled away from the guide rail 12 by the return springs 27.

In addition, when the car brake 19 is operated, a movement of the car 8 relative to the two brake shoes 24 is allowed in the ascending and descending direction of the car, within a movement range between a lower limit position where the two brake arms 22 are in the most extended state to an upper limit position where the two brake arms 22 are in the most contracted state, whereas a relative movement of these beyond the movement range is restricted.

Moreover, when the car brake 19 is released, that is, when there is no load on the car brake 19, the two brake shoes 24 are held by the coil springs 33 at the positions where the position of the car 8 relative to the said two brake shoes 24 is an intermediate position within the above-mentioned movement range. In other words, after the operation of the car brake 19, the car 8 can be moved either up or down relative to two brake shoes 24.

Figure 5 is a flow chart showing one example of processing that could be performed by the elevator controller 10 from the arrival of the car 8 at a prescribed destination floor to the start of its travel. In addition, Figure 6 shows the operation of the car brake 19 from the arrival of the car 8 at a prescribed destination floor to the start of its travel.

As shown in Figure 6(a), when the car 8 travels in a state in which the car brake 19 is released and then arrives at a prescribed destination floor (step Sl of Figure 5), the elevator controller 10 operates the car brake 19 in addition to the hoist brake 7 (step S2 of Figure 5) as shown in Figure 6(b), and opens the doorway 16a of the car compartment 16 by opening the two slide doors 17 by means of the door operator 18 (step S3 of Figure 5).

Here, needless to say, if passengers or baggage enter or leave the car compartment 16 after the doorway of the car compartment 16 is opened, the car 8 may be moved vertically by the expansion and contraction of the main rope 2. In conjunction with the displacement of the car 8, the two brake arms 22 generate an attenuating force while expanding and contracting, suppressing the oscillation of the car 8. Specifically, for example, if the live load of the car 8 is increased as a result of passengers or baggage entering and leaving, the car 8 is displaced downward by the lengthening of the main rope 2. In this case, as shown in Figure 6(c), the two brake arms 22 respectively generate attenuating forces while being expanded, suppressing the oscillation of the car 8.

Next, Figure 7 is a graph showing the displacement of the car due to changes in the live load. Figure 7(a) is a graph showing the displacement of a car in an elevator apparatus having no car brake as a comparative example, and Figure 7(b) is a graph showing the displacement of the car 8 in an embodiment of the present invention. As shown in Figure 7, in the comparative example shown in Figure 7(a), the car 8 experiences a relatively large oscillation from the change in live load. On the other hand, in this embodiment shown in Figure 7(b), it is apparent that the oscillation due to the change in live load of the car 8 is largely suppressed, compared with the comparative example, by the dampers 30 of the two brake arms 22.

In addition, if the amount of misalignment of the floor surface position of the car 8 received from the car position detector 14 exceeds a prescribed threshold as a result of the displacement of the car 8 in this manner (step S4 of Figure 5), the elevator controller 10 performs a re-leveling operation (floor realigning operation) for aligning the floor surface position of the car 8 with the floor surface position of a landing not shown in the figure (steps S5-7 of Figure 5). Moreover, at step S4 of Figure 5, if the result of the decision is NO, flow proceeds to step S8 of Figure 5 without a re-leveling operation. Specifically, this re-leveling operation is carried out by releasing the hoist brake 7 and rotationally driving the hoist motor 6 in a state in which the car brake 19 is being operated. In other words, even during this re-leveling operation, as shown in Figure 6(d), the two brake arms 22 are expanded and contracted in conjunction with the movement of the car 8 while generating an attenuating force, suppressing the oscillation of the car 8.

Next, the elevator controller 10 decides whether or not the doorway 16a of the car compartment 16 is to be closed (step S8 of Figure 5). If the result of this decision is YES, the doorway 16a of the car compartment 16 is closed (step S9 of Figure 5), the car brake 19 and the hoist brake 7 are released as shown in Figure 6(e) (step SlO of Figure 5), and travel of the car 8 is started (step SIl of Figure 5). Here, as is well known, at step S8 of Figure 5 a not-shown door closing button, installed in the car compartment 16 is pressed, or after opening the doorway 16a of the car compartment 16, the doorway 16a is closed after a prescribed time has lapsed. In addition, if the result of the decision at step S8 of Figure 5 is NO, flow returns to step S4 of Figure 5.

In this embodiment, as described above, since the change in live load of the car 8 is absorbed by the expansion and contraction of the main rope 2, the load that is shared by the car brake 19 is minimal, so that a so-called starting shock in which the car 8 moves when the car brake 19 is released at step SlO of Figure 5 can be reduced.

Moreover, if the car 8 operates abnormally during operation of the car brake 19 and moves beyond the movement range of said car 8, the two brake arms 22 are in the most expanded state or most contracted state, so that a further movement of the car 8 can be prevented.

Therefore, according to this embodiment, the oscillation of the car 8 passengers or baggage entering/leaving can be suppressed by the dampers 30 provided to the two brake arms 22, and a so-called starting shock at the car brake 19 when it is released can also be reduced, improving the comfort of riding the elevator.

Claims

1 . A brake assembly for an elevator car in an elevator apparatus, wherein the car is suspended from a main rope guided by a fixed member attached to the peripheral wall of a hoistway, the brake assembly comprising:

a braking member that contacts the fixed member so that the car can be moved relative to the braking member within a prescribed allowable range in the ascending and descending direction of the car, and

an attenuator that attenuates oscillation of the car.

2 . The elevator apparatus of Claim 1, characterized by the fact that the braking member of the car brake can be connected to the car via an attenuator that can expand and contract in the ascending and descending direction of the car, and the attenuator can expand and contract while generating an attenuating force when the car moves up and down relative to the braking member of the car brake.

3 . The elevator apparatus of Claim 1, characterized by the fact that when the car brake is released, the braking member of the car brake is held at the position where the position of the car relative to the braking member of the car brake assumes an intermediate position in the movement range, and after the operation of the car brake, the car can move both up and down relative to the braking member of the car brake.

4 . The elevator apparatus of Claim 1, characterized by the fact that the braking member of the car brake is arranged opposite to guide rails serving as the fixed member for guiding the ascent and descent of the car, and the braking member contacts the guide rails and brakes the car.

5 . The elevator apparatus of Claim 4, characterized by the fact that the contact surface of the braking member in contact with at least the guide rails is formed of a permanently magnetic material, and when the car brake is operated, the braking member is attracted to the guide rails by its magnetic force.

6 . The elevator apparatus of Claim 1, characterized by the fact that a hoist having a drive sheave around which the main rope runs has a hoist brake, separate from the car brake, for braking the drive sheave.

7 . The elevator apparatus of Claim 6, characterized by the fact that when the car arrives at a prescribed destination floor, the doorway of the car is opened after both the car brake and hoist brake are operated.