SG185238A1 - Brake releasing machine and elevator - Google Patents

Abstract

BRAKE RELEASING MACHINE AND ELEVATORAbstractA brake releasing machine releasing a brake spring, a force of the brake spring being applied to a brake lever through an end of brake spring, another end of brake spring being kept stationary to urge the brake lever, has a first bracket to be arranged in the vicinity of the end to bear at least a part of the force, a second bracket in the vicinity of the another end to face to the first bracket, a supporting part holding the first and second brackets with respect to each other to keep a distance therebetween constant, and an actuator mounted on the second bracket and including a movable part movable in a direction in which the first and second brackets face to each other, and the brake spring is arranged between the first bracket and the movable part so that the brake spring is compressed in accordance with a decrease in distance between the first bracket and the movable part.Figure: 3

Description

BRAKE RELEASING MACHINE AND ELEVATOR

Background of the Invention

The present invention relates to a brake releasing machine for releasing a brake lever for braking an elevator, and an elevator using the brake releasing machine.

In a brake releasing machine attached to a traction machine for hoisting of an elevator, a brake lever of a brake machine is released compulsorily, for example, for maintenance and inspection. As a releasing machine for compulsorily releasing the brake lever, an electromagnet for driving a brake during an operation of the elevator is directly actuated.

For example, in JP-A-4-59585, a releasing lever is pressed by the electromagnet, and an operating rod is arranged to directly press an actuating rod for driving the brake lever.

In this case, an operator grasps and presses downward the operating rod to press the releasing lever through the actuating rod so that the brake lever is released compulsorily.

Further, JP-A-2000-219464 discloses a machine for making an electromagnetic brake of specified type release a braking force. In this electromagnetic brake, a plunger driven by excitation of the electromagnet and a main lever of the brake are connected to each other by an L-shaped lever. A motion of the plunger is transmitted to the main lever by a rotation of the

L-shaped lever to release the main lever.

In the releasing machine of JP-A-2000-219464, the main lever of the electromagnetic brake of specified type is released by rotating the I.-shaped lever compulsorily with pressing the L-shaped lever and an upper end of the main level toward each other.

Brief Summary of the Invention

In the magnetic brake disclosed by each of JP-A-2000-219464 and JP-A-2000- 219464, the brake levers as a pair are actuated simultaneously by movements of the actuating rod or the plunger. Therefore, in the brake releasing machine of JP-A-2000-219464 wherein the actuating rod is directly operated, the pair of the brake levers is released simultaneously.

On the other hand, in recent years, it is required for safety that the elevator is sufficiently braked by only one of the brake levers even when the other one of the brake levers does not move in a case of, for example, breakdown.

Therefore, it is preferable for the brake releasing machine that the braking force can be inspected when each of the brake levers is actuated independently to release respective one of the brakes during the maintenance, inspection or the like. However, in the brake

-0- releasing machine of JP-A-2000-219464, since the brake levers as the pair are simultaneously released, the braking force of each of the brake lever cannot be inspected.

Further, in JP-A-2000-219464, the L-shaped lever and the upper end of the main level are pressed toward each other. This brake releasing machine wherein the main lever is released by rotating compulsorily the L-shaped lever, is applicable to only the brake machine wherein the L-shaped lever and the main lever are pressed toward each other.

With taking the above problems into consideration, an object of the present invention is to provide a brake releasing machine wherein each of braking portions of a brake machine is actuated independently so that the brake releasing machine is enabled to be applicable to the brake machine even in a case that the brake machine does not have the L- shaped lever.

According to the invention, for solving the above problems, a brake releasing machine for releasing a brake machine having a brake spring, through an end of which brake spring a force of the brake spring is applied to a brake lever, and another end of which brake spring is kept stationary so that the brake lever is movable by the spring force with respect to the another end, comprises a first bracket to be arranged in the vicinity of the end to bear at least a part of the spring force, and a second bracket in the vicinity of the another end to face to the first bracket.

The brake releasing machine further comprises a supporting member holding the first and second brackets with respect to each other to keep a distance therebetween fixedly, and an actuator including a movable portion movable in a direction in which the first and second brackets face to each other.

In addition, the brake spring is arranged between the first bracket and the movable portion so that the brake spring is compressed in accordance with a decrease in distance between the first bracket and the movable portion.

According to the invention, since the brake spring urging each of the brake levers is arranged between the first bracket and the movable portion, the brake releasing machine of the invention is applicable to any type of the brake machine irrespective of a difference in structure among the brake machines.

Further, since each of the brake springs is directly compressed, each of the brake levers can be released independently.

In addition, an elevator of the invention comprises a cage descending and ascending in a hoistway, a balance weight connected to the cage through a main rope, and a traction machine on which the main rope is wound to ascend and descend the cage. The above mentioned brake releasing machine is mounted on the elevator.

According to the invention, since the brake spring urging each of the brake levers is arranged between the first bracket and the movable portion to be directly compressed, each of the brake lever corresponding to respective one of the brake spring can be released independently. Further, the brake releasing machine of the invention is applicable to any type of the brake machine irrespective of the difference in structure among the brake machines.

Brief Description of the Several Views of the Drawings

Fig. 1 is a schematic view showing an elevator using a brake releasing machine as a first embodiment of the invention.

Fig. 2 is a schematic view showing the brake releasing machine.

Fig. 3 is a schematic view showing the brake releasing machine as the first embodiment of the invention.

Fig. 4 is a schematic view showing a brake machine on which the brake releasing machine as the first embodiment of the invention is mounted.

Fig. 5 is a partially cross sectional view showing the brake machine and the brake releasing machine shown in Fig. 4.

Fig. 6 is an explanation view showing a brake releasing motion by the brake releasing machine as the first embodiment of the invention.

Fig. 7 is an explanation view showing a brake releasing motion by the brake releasing machine as a second embodiment of the invention.

Fig. 8 is an explanation view showing the brake machine on which the brake releasing machine as a third embodiment of the invention is mounted.

Fig. 9 is an explanation view showing a motion of a pair of the brake levers simultaneously released by the brake releasing machine as the first embodiment of the invention.

Detailed Description of the Invention

Hereafter, best modes as embodiments of the invention will be explained, however, a scope of the invention is not limited within the below embodiments. The explanation is done along the following order. 1. First embodiment (wherein a brake spring is compressed by pressing a rod) 2. Second embodiment (wherein the brake spring is compressed by pressing both ends of the brake spring toward each other) 3. Third embodiment (wherein both of a brake lever and the brake spring are compressed) 4. Fourth embodiment (wherein releasing simultaneously both of the brake levers) 1. First embodiment (wherein a brake spring is compressed by pressing a rod)

Fig. 1 is a schematic view showing an elevator 400 in which as the first embodiment is incorporated.

The elevator 400 has a cage 230 ascending and descending in a hoistway 220 in a building construction, a balance weight 250 connected to the cage 230 through a main rope 240, a traction machine 210 which is arranged at a top of the hoistway 220 and on which the main rope 240 is wound to ascend and descend the cage 230, and a deflecting wheel 260 arranged in the vicinity of the traction machine 210 to hold the main rope 240 thereon. The brake releasing machine 100 is mounted on a brake machine of the traction machine 210.

Fig. 2 is a schematic front view showing the brake machine 270 mounted on the traction machine 210. The brake machine 270 has a pair of brake levers 2a, 2b between which a side surface of a brake drum 1 of the traction machine 210 is arranged, a pair of brake shoes 3a, 3b arranged on the brake levers 2a, 2b respectively to be pressed against the brake drum 1 so that a braking force is applied to the elevator, a pair of brake rods 6a, 6b extending through upper ends of the brake levers 2a, 2b respectively, and a driving part 10 connected to ends of the brake rods 6a, 6b and driving the brake levers 2a, 2b against respective spring forces of brake springs

Sa, 5b.

Lower ends of the brake levers 2a, 2b are supported on shaft pins 4a, 4b respectively in a rotatable manner. The brake shoes 3a, 3b mounted on the brake levers 2a, 2b are pressed against the brake drum 1 by rotations of the brake levers 2a, 2b to generate a braking force.

The brake rods 6a, 6b extend through the upper ends of the brake levers 2a, 2b respectively, and flange portions 7a, 7b of nuts or the like are mounted on ends of the other ends of the brake rods 6a, 6b to be contactable with spring washers 8a, 8b on surfaces of the flange portions 7a, 7b facing to the brake drum 1.

Each of the brake springs 5a, 5b is arranged between respective one of the spring washers 8a, 8b and respective one of the brake levers 2a, 2b. The brake rods 6a, 6b extend through the brake springs 5a, 5b respectively.

Ends of the brake springs 5a, 5b are contactable with the spring washers 8a, 8b to be prevented from moving beyond the spring washers 8a, 8b in a direction away from the brake drum 1. The brake springs 5a, 5b urge the brake levers respectively toward the driving part 10 so that the brake shoes 3a, 3b are pressed against the brake drum 1.

The ends of the brake rods 6a, 6b in the vicinity of the brake drum 1 are connected to the driving part 10 for driving rotationally the brake levers 2a, 2b. The driving part 10 has plungers 9a, 9b to move the brake levers 2a, 2b to be released from the brake drum, and electromagnets 10a for driving the plungers 9a, 9b.

The electromagnets 10a may be of any type capable of moving forward and backward the plungers 9a, 9b with excitation of coils.

The brake levers 2a, 2b are movable in respective directions shown by arrow marks Al, A2 in accordance with respective motions of the plungers 9a, 9b so that the driving force of the brake springs 5a, 5b are adjusted to control the braking force during elevator operation.

Fig. 3 is a schematic view showing the brake releasing machine 100 for releasing a braking of the brake machine 270.

The brake releasing machine 100 of this embodiment has a first bracket bearing a force of the brake spring Sa and a second bracket 12 facing to the first bracket 11. The first bracket 11 is arranged in the vicinity of an end of the brake spring 5a, and the second bracket 12 is arranged in the vicinity of another end of the brake spring 5a.

Supporting parts 13 keep a distance between the first bracket 11 and the second bracket 12, and an actuator 14 is mounted on the second bracket 12.

The actuator 14 has a movable portion 14b movable in a direction in which the first bracket 11 and the second bracket 12 facing to each other.

In the brake releasing machine 100 of this embodiment, as mentioned below, the brake spring 5a is arranged between the first bracket 11 and the movable portion 14b to be compressed therebetween so that the braking is released.

Shapes and materials of the first bracket 11, the second bracket 12 and the supporting parts 13 do not need to be limited if they can bear a reaction force caused by the compression of the brake spring.

Further, in this embodiment, the supporting parts 13 extend through the first bracket 11 and the second bracket 12. The supporting parts 13 engage with respective nuts 16 contactable with the first bracket 11 and the second bracket 12 respectively to keep a distance therebetween fixedly.

By rotating the nuts 16, the distance between the first bracket 11 and the second bracket 12 can be adjusted.

Since the distance between the first bracket 11 and the second bracket 12 can be adjusted by the nuts 16 as an adjusting mechanism, the brake spring of any length can be arranged between the first bracket 11 and the second bracket 12 so that the brake releasing machine 100 of this embodiment is applicable to any type of the brake machine.

The first bracket 11 has a notch portion 17 through which the brake lever 2a, the brake rod 6a and so forth can extend as mentioned below.

The actuator 14 is arranged on a surface of the second bracket 12 facing to the first bracket 11. The actuator 14 has an actuator body 14a mounted on the second bracket 12 and the movable portion 14b driven by the actuator body 14a in the direction wherein the first bracket 11 and the second bracket 12 face to each other.

For example, a cylinder device may be used as the actuator 14. The actuator body 14a may include a driving source 14 such as a hydraulic device or the like to move the movable portion 14b forward and backward. The movable portion 14b is, for example, a plunger movable in the direction wherein the first bracket 11 and the second bracket 12 face to each other. That is, the movable portion 14b is movable against an urging force (spring force) of the brake spring 5a.

The brake releasing machine 100 mounted on the brake machine 270 (refer to Fig. 2) is shown in each of Figs. 4 and 5. Fig. 4 is a side view of the brake releasing machine 100 mounted on the brake machine 270, and Fig. 5 is a cross sectional view taken along line A-A' in

Fig. 4.

The upper end of the brake lever 2a extends through the notch portion 17 of the first bracket 11, and the first bracket 11 extends to cover the upper end of the brake lever 2a.

Incidentally, the first bracket 11 can slide on the brake lever 2a at the notch portion 17 in a direction indicated by an arrow mark A3.

An end 51a of the brake spring 5a facing to the brake drum 1 (refer to Fig. 2) contacts the bracket 11 and the brake lever 2a.

The movable portion 14b of the actuator 14 contacts an end of the brake rod 6a extending through the brake lever 2a and the brake spring 5a, and the end of the brake rod 6a opposite to the brake lever 2a through the brake rod 6a.

An end 51b of the brake spring 5a contacts the spring washer 8a to be fixedly held, and the spring washer 8a contacts the flange portion 7a fixed to the brake rod 6a. That is, the brake spring 5a is arranged between the first bracket 11 and the movable portion 14b through the brake rod 6a, the flange portion 7a and the spring washer 8a.

The brake releasing machine 100 is prevented from being moved downward at the second bracket 12 by its own weight so that the end of the braking rod 6a and the movable portion 14b are prevented from being disengaged from each other, by any structure. For example, the movable portion 14b may have a concave area receiving the end of the braking rod 6a, the second bracket 12 may be supported in a horizontally movable manner by a support part fixed to an adjacent place, or the second bracket 12 may be mounted on a table.

A motion of the brake releasing machine 100 as the embodiment is explained with making reference to Fig. 6.

A part of Fig. 6 as a side view shows the brake releasing machine 100 as the embodiment mounted on the brake spring 5a, wherein the end 51a of the brake spring 5a in the vicinity of the brake drum 1 (refer to Fig. 2) contacts both of the first bracket 11 and the brake lever 2a, and urges the brake lever 2a toward the driving part 10 to brake the elevator.

Each of B and C parts of Fig. 6 shows the movable portion 14b moved toward the first bracket 11 by a distance d1 with a drive source 15 (not shown).

As indicated by an arrow mark A4, the movable portion 14b projects from the actuator body 14 toward the first bracket 11 by the distance d1 while pressing the end of the brake rod 6a.

On the other hand, an opposite end of the brake rod 6a is fixed to the driving part 10 for driving the brake levers 2a, 2b during the normal operation of the elevator. Therefore, the brake rod 6a is not moved when being pressed by the movable part 14b.

Since the brake rod 6a is not moved when the movable part 14b presses the end of the brake rod 6a, the second bracket 12 with the movable part 14 mounted thereon is pushed out in a direction indicated by an arrow mark AS to be moved by a distance d1.

On the other hand, the first bracket 11 is connected fixedly to the second bracket 12 by the supporting parts 13 to keep a distance between the first bracket 11 and the second bracket 12 constant. Therefore, when the second bracket 12 moves in the direction indicated by the arrow mark AS by the distance d1, the first bracket 11 moves by the distance d1 in a direction indicated by an arrow mark A6 equal to the direction indicated by the arrow mark AS.

Since the end 51a of the brake spring 5a contacts the first bracket 11, when the first bracket 11 moves by the distance d1 in the direction indicated by the arrow mark A6, the brake spring 5a is compressed by the distance d1.

That is, in this embodiment, a pressing force applied to the brake rod 6a by the movable part 14b is converted to a pressing force applied to the brake spring 5a by the first bracket 11 through the second bracket 12 and the supporting parts 13.

By compressing the brake spring 5a by the distance d1, the brake spring 5a is separated from the brake lever 2a by the compressed distance d1. Accordingly, the brake lever 2a is released from being compressed by the first bracket 11.

It is preferable for the brake lever 2a to be formed in such a manner that a center of gravity thereof is more distant from the brake drum 1 than the shaft pin 4a supporting the brake lever 2a in a rotatable manner (refer to fig. 2). When by compressing the brake spring, the brake spring 5a is made distant from the brake lever 2a by the distance d1, as shown in a part

C of Fig. 6, the brake lever 2a is moved by its own weight by the distance d1 in a direction indicated by an arrow mark A7. Therefore, the brake lever 2a is released.

Incidentally, in a part B of Fig. 6, it is shown with rhetorically increasing the distance d1 that the bracket 11 is released from the upper end of the brake lever 2a when the brake spring 5a is compressed. Actually, in response to every small value Ad by which the movable part 14b moves, the brake lever 2a rotates in accordance with the small value Ad.

Therefore, the first bracket 11 slides on the brake lever 2a while being prevented from being released from the upper end of the brake lever 2a.

Further, when the movable part 14 is moved rapidly, for example, a guide part of rail-shape may be arranged on the upper end of the brake lever 2a to enable the first bracket 11 to slide on the guide part. Further, the guide part may be fixed to the first bracket 11 to enable the guide part to slide on the upper end of the brake lever 2a. Accordingly, the first bracket 11 is securely prevented from falling.

As mentioned above, in the brake releasing machine 100 as the embodiment of the invention, since the brake spring is directly pressed to be compressed, the brake releasing machine 100 of the invention is applicable to various types of the brake machine having the brake springs respectively.

Further, the brake releasing machine of the invention can be mounted on each of the brake springs urging the brake levers respectively. Therefore, each of the brake levers can be released to inspect and evaluate the braking force of the brake lever independently. 2. Second embodiment (wherein the brake spring is compressed by pressing both ends of the brake spring toward each other)

While the brake spring is compressed by pressing the brake rod with the movable part in the first embodiment, the end of the brake spring may be directly pressed by the movable part.

A part of Fig. 7 is an explanation view showing a brake releasing machine 200 as the second embodiment mounted on a brake machine 270 (refer to Fig. 2).

The brake releasing machine 200 as this embodiment has a first bracket 21 bearing the force of the brake spring 5a and a second bracket 22 arranged to be opposite to the first bracket 21. The first bracket 21 is arranged in the vicinity of the one of the ends of the brake spring 5a, and the second bracket 2 is arranged in the vicinity of the another one of the ends of the brake spring 5b.

The brake releasing machine 200 further has supporting parts 23 keeping a distance between the first bracket 21 and the second bracket 22, and an actuator 24 mounted on the second bracket 22.

The actuator 24 has a movable part 24b movable in a direction in which the first bracket 21 and the second bracket 22 face to each other.

Structures of the first bracket 21, the second bracket 22, the supporting parts 23, adjusting mechanism 26 and so forth may be equal to those of the first embodiments. The first bracket 21 has a notch portion 27 to receive therein an upper end of the brake lever 2a similarly to the first embodiment. Further, the end 51a of the brake spring 5a contact both of the first bracket 21 and the brake lever 2a.

Incidentally, in this embodiment, a shape of the movable part 24b is cylindrical, and the movable part 24 contacts the spring washer 8a.

The cylinder device, for example, may be used as the actuator 24. An actuator body 24a is driven by, for example, a power source such as the hydraulic device to move forward and backward the movable part 24b. The movable part 24b is, for example, the plunger movable in the direction in which the first bracket 21 and the second bracket 22 face to each other. That is, the movable part 24b is movable against the force (spring force) of the brake spring Sa.

In a B part of Fig. 7, a condition after the movable part has moved toward the first bracket 21 by a distance d2, is shown.

The movable part 24b is moved in a direction indicated by an arrow mark A8 to press the brake spring 5a through the spring washer 8a. The end 51 a of the brake spring 5a contacts the first bracket 21 to be fixedly held. Therefore, the brake spring 51 is compressed between the movable part 24b and the first bracket 21.

By compressing the brake spring 5a, a clearance corresponding to the compressed distance d2 is formed between the spring washer 8a and the flange portion 7a.

In this situation, a system consisting of the brake releasing machine 200 as the embodiment of the invention, the spring washer 8a, the brake spring 5a and the brake laver 2a is prevented from being restrained axially by the brake rod 6a to be free with respect to the brake rod 6a.

On the other hand, as mentioned above, the center of gravity of the brake lever 2a is more distant from the shaft pin 4a (refer to Fig. 2) than the brake drum 1. Therefore, the brake lever 2a is urged by its own weight to rotate in a direction indicated by an arrow mark A9 as shown in a part C of Fig. 7.

In such situation, since the system consisting of the brake releasing machine 200, the spring washer 8a, the brake spring 5a and the brake laver 2a is free with respect to the brake rod 6a, the whole of the system moves in a direction indicated by an arrow mark A10.

Subsequently, such movement is stopped when the spring washer 8a contacts the flange portion 7a. Therefore, the brake lever 2a moves by the distance d2 to release the braking.

In this embodiment, since the movable part 24b directly presses the brake spring

Sa, the pressing force of the movable part 24b is used only to compress the brake spring Sa. 3. Third embodiment (wherein both of the brake lever and the brake spring are compressed)

Further, both of the brake lever and the brake spring may be compressed to release the braking. Fig. 8 is an explanation view showing a situation wherein a brake releasing machine 300 as a third embodiment of the invention is mounted on a brake machine 270 (refer to

Fig. 2).

The brake releasing machine 300 as this embodiment has a first bracket 31 bearing the force of the brake spring 5a, and a second bracket 32 facing to the first bracket 31.

The first bracket 31 is arranged in the vicinity of the one of the ends of the brake spring 5a, and the second bracket 32 is arranged in the vicinity of the another one of the ends of the brake spring Sa.

Further, the brake releasing machine 300 has supporting parts 33 keeping the distance between the first bracket 31 and the second bracket 32 constant, and an actuator 34 mounted on the second bracket 32.

The actuator 34 has an actuator body 34a mounted on the second bracket 32, and a movable part 34b movable in a direction in which the first bracket 31 and the second bracket 32 face to each other.

Structures of the second bracket 32, the supporting parts 33, adjusting mechanism 36, the actuator 34 and so forth may be equal to those of the first embodiments. Incidentally, the first bracket 31 has a notch portion 37 to receive therein only the brake rod 6a.

Further, a width of the notch portion 37 is larger than a diameter of the brake rod 6a and smaller than a width of the brake lever 2a. Therefore, a surface 31a of the first bracket 31 facing to the second bracket 32 contacts the brake lever 2a. In this situation, the first bracket 31 may be fixed by a bolt or the like to the brake lever 2a, or may have a protrusion extending from the surface 31a toward the second bracket 32 and being capable of engaging with the upper end of the brake lever 2a.

The movable part 34a contacts the end of the brake rod 6a. When the movable part 34b is driven toward the first bracket 31 by a driving source such as the hydraulic device or the like not shown, the first bracket 31 is urged in a direction indicated by an arrow mark A11 with the same principle as the first embodiment (refer to Fig. 6). In this situation, the surface 31a of the first bracket 31 contacts the brake lever 2a to press the brake lever in the direction indicated by the arrow mark A11.

By pressing the brake lever 2a with the first bracket 31, the end of the brake spring Sa facing to the brake drum 1 (not shown, refer to Fig. 2) is pressed. Since the another end of the brake spring 5a is held stationary by the spring washer 8a, the brake spring 5a is compressed.

As mentioned above, in this embodiment, the brake lever 2a and the brake spring

Sa is arranged between the first bracket 31 and the movable part 34b. That is, by mounting the brake releasing machine of this embodiment as mentioned above to clamp the brake lever 2a and the brake spring 5a to compress the brake spring 5a, the braking is released. 4. Fourth embodiment (wherein releasing simultaneously both of the brake levers)

Incidentally, the brake releasing machine of the invention can release simultaneously both of the brake levers.

For example, an example for releasing simultaneously both of the brake levers with the brake releasing machine 100 as the first embodiment (refer to Fig. 3) is shown in Fig. 9.

A brake machine shown in Fig. 9 has a pair of brake levers 2c, 2d arranged to clamp side surfaces of the brake drum 1a of the traction machine, and brake shoes 3c, 3d arranged on the brake levers 2c, 2d respectively to be pressed against the brake drum 1a to apply a braking force to the elevator.

Further, the brake machine has a brake rod 6¢ extending through upper ends of the brake levers 2c, 2d. Incidentally, the brake rod 6¢ and the brake lever 2d are fixed to each other. Lower ends of the brake levers 2c, 2d are supported by shaft pins 4c, 4d respectively in a rotatable manner.

A brake spring 5c is arranged in the vicinity of the brake lever 2c, and an end of the brake spring 5c more distant from the brake drum 1a than another end of the brake spring 5c is held stationary through a spring washer 8c by a flange 7c mounted on the brake rod 6c.

Further, the another end of the brake spring 5c closer to the brake drum 1a than the end thereof contact the brake lever 2c.

In this brake machine 280, by pressing the brake lever 2c with the another end of the brake spring Sc closer to the brake drum 1a than the end thereof contact the brake lever 2c, the brake shoe 3c mounted on the brake lever 2c is pressed against the brake drum.

Further, by pressing the flange 7c of the brake rod 6¢ with the end of the brake spring Sc more distant from the brake drum 1a than the another end of the brake spring Sc, the brake rod 6c is pressed in a direction indicated with an arrow mark A12. Since the brake rod 6¢ and the brake lever 2d are fixed to each other, by pushing out the brake rod 6¢, the brake lever 2d is rotated in the direction indicated with the arrow mark A12 to press the brake shoe 3d mounted on the brake lever 2d against the brake drum la. Therefore, a braking force for braking the elevator is generated.

The brake releasing machine 100 as the first embodiment is mounted on the brake spring Sc of the brake machine 280.

A manner for mounting the brake releasing machine 100 is similar to that of the first embodiment (refer to Fig. 5). That is, the notch portion of the first bracket receives therein the upper end of the brake lever 2c and the brake rod 6c, and the another end of the brake spring 5c closer to the brake drum 1a than the end thereof contact both of the first bracket 11 and the brake lever 2c.

Further, the movable part 14b of the brake releasing machine 100 contacts the end of the brake rod 6c.

By moving the movable part 14b toward the first bracket 11, with the same principle as the first embodiment, the first bracket 11 presses the another end of the brake spring 5c closer to the brake drum 1a than the end thereof. The brake spring Sc is clamped between the movable part 14b and the first bracket 11 to be compressed, and the brake lever 2c is rotated by its own weight in the direction indicated by the arrow mark A11, so that the braking is released.

On the other hand, the movable part 14b moves toward the first bracket 11 to press the end of the brake rod 6¢, so that the brake rod 6c is pushed out in a direction indicated by an arrow mark A13.

Since the brake lever 2d is fixed to the brake rod 6¢, when the brake rod 6c is pushed out, the brake lever 2d rotates in the direction indicated by an arrow mark A13.

Therefore, the brake rod 2d is released.

When the brake rod is fixed to one of the brake levers, and both of the brake levers are urged by the single brake spring as performed in the brake machine 280, the brake releasing machine of the invention is capable of simultaneously releasing both of the brake levers.

Incidentally, although the example using the brake releasing machine 100 as the first embodiment is mentioned above, each of the brake releasing machines 200, 300 as the second embodiment (refer to Fig. 7) and the third embodiment (refer to Fig. 8) can be used.

The embodiments of the brake releasing machines of the invention are described above. The invention covers various modifications within the substance of the invention recited in claims without being limited by the above embodiments. Further, although operations of the first, second and third embodiments are explained in a situation wherein the brake releasing machine is arranged in the vicinity of the brake spring 5a, the brake releasing machine can operate similarly when the brake releasing machine is arranged in the vicinity of the brake spring 5b.

Claims (9)

Claims :

1. A brake releasing machine for releasing a brake spring, through an end of which brake spring a force of the brake spring is applied to a brake lever, and another end of which brake spring is kept stationary to urge the brake lever through the end, comprising a first bracket to be arranged in the vicinity of the end to bear at least a part of the force, a second bracket in the vicinity of the another end to face to the first bracket, a supporting part holding the first and second brackets with respect to each other to keep a distance therebetween constant, and an actuator mounted on the second bracket and including a movable part movable in a direction in which the first and second brackets face to each other, wherein the brake spring is capable of being arranged between the first bracket and the movable part so that the brake spring is compressed in accordance with a decrease in distance between the first bracket and the movable part.

2. The brake releasing machine according to claim 1, wherein a surface of the first bracket facing to the second bracket is contactable with the end of the brake spring.

3. The brake releasing machine according to claim 1, wherein the brake lever is capable of being arranged between the end of the brake spring and a surface of the first bracket facing to the second bracket.

4. The brake releasing machine according to claim 2 or 3, wherein the movable part is arranged to press an end of a brake rod extending through the brake lever.

5. The brake releasing machine according to claim 2 or 3, wherein the movable part is arranged to press the another end of the brake spring.

6. The brake releasing machine according to any one of claims 1-5, wherein the first bracket has a notch portion to receive therein at least one of the brake lever and the brake rod.

7. The brake releasing machine according to any one of claims 1-6, wherein the machine further comprises a mechanism for adjusting the distance between the first bracket and the second bracket.

8. The brake releasing machine according to any one of claims 1-7, wherein the movable part includes a hydraulic device.

9. An elevator comprising, a cage ascending and descending in a hoistway, a balance weight connected to the cage through a main rope, a traction machine on which the main rope is wound to ascend and descend the cage, and a brake releasing machine for releasing a brake spring, through an end of which brake spring a force of the brake spring is applied to a brake lever, and another end of which brake spring is kept stationary to urge the brake lever through the end, having a first bracket to be arranged in the vicinity of the end to bear at least a part of the force, a second bracket in the vicinity of the another end to face to the first bracket, a supporting part holding the first and second brackets with respect to each other to keep a distance therebetween constant, and an actuator mounted on the second bracket and including a movable part movable in a direction in which the first and second brackets face to each other, wherein the brake spring is capable of being arranged between the first bracket and the movable part so that the brake spring is compressed in accordance with a decrease in distance between the first bracket and the movable part.