JP5919856B2 - Braking device for elevator hoisting machine - Google Patents

Description

The present invention relates to a brake device for an elevator hoisting machine.

The elevator hoisting machine is provided with a sheave that rotates and a braking device that brakes the rotation of the sheave. A car is suspended from a rope wound around the sheave. The braking device is provided with, for example, a brake disk, a friction material, a spring, and an electromagnet. The brake disc is allowed to rotate integrally with the sheave, and the friction material is pressed against the brake disc by the elastic force of the spring, or the friction material is pulled away from the brake disc by the attraction force of the electromagnet against the elastic force of the spring. It is.

When raising and lowering the car, the friction material is pulled away from the brake disc so that the brake disc and the sheave can rotate, and the sheave is driven to rotate. When stopping the car, the friction material is pressed against the brake disk to stop the rotation of the brake disk and the sheave. When a large braking force is required depending on the specifications of the elevator, generally, the elastic force of the spring and the attractive force of the electromagnet are increased, and the braking device is also large.
(For example, see Patent Document 1)

JP 2006-52035 (FIG. 1)

By the way, in the elevator, the speed monitoring unit monitors the speed of the car, and if it detects that the speed of the car exceeds the specified value for some reason, the speed monitoring part outputs a braking signal to operate the braking device, and detects it. The car is stopped within a predetermined distance from the current car position. However, during the period from the detection until the braking device operates and the braking force begins to work, that is, the friction material separated from the brake disk moves toward the brake disk and presses against the brake disk, and the braking force begins to work. In the meantime, the car moves up and down without being braked, resulting in a free running distance.

Therefore, a part of the predetermined distance for the car to stop is spent as the free running distance, and the braking distance where the braking force is actually applied is shortened. Further, it is necessary to generate a large braking force corresponding to the shortening of the braking distance, and the braking device has to be enlarged.

The present invention has been made to solve such a problem, and stops the car within a predetermined distance from the position of the car when the car speed monitoring unit detects that the car speed exceeds a specified value. It is an object of the present invention to provide a braking device for an elevator hoisting machine that can reduce the braking force required for reducing the size of the braking device.

The brake system for an elevator hoist according to the present invention is connected to one end of a suspension means that is wound around a sheave rotatably provided on the hoist so that the speed of a car that moves up and down with the rotation of the sheave is increased. A first speed monitoring means for monitoring and generating a braking signal when it detects that the speed exceeds a specified value, and a first braking force provided on the hoisting machine and having a first braking force for receiving the braking signal and suppressing the speed. A braking means and a second braking means that is provided in the hoist and has a second braking force that receives the braking signal and brakes the lifting, and the first braking force is smaller than the second braking force, The first braking force starts braking earlier than the second braking force, and the car is stopped within a predetermined distance from the position of the car at the time point detected by the first braking means and the second braking means.

According to the present invention, when the speed of the car that moves up and down with the rotation of the sheave exceeds the specified value, the speed monitoring means detects and generates a braking signal. In response to this braking signal, the first braking means first suppresses the speed at which the car moves up and down with the first braking force. Next, in addition to the first braking means, the second braking means starts the raising / lowering braking of the car with the second braking force and stops the car. When the car is stopped within a predetermined distance by the first braking force and the second braking force, the first braking force first suppresses the speed of the car, so that the first braking force and the second braking force The mileage of the car can be shortened until both braking forces start to work. That is, of the predetermined distance for stopping, the idle running distance where the braking force does not work is shortened, and the braking distance where the braking force works is lengthened, so that the necessary braking force is reduced, and the braking device can be downsized.

According to the present invention, the braking force required to stop the car within a predetermined distance from the position of the car at the time when the car speed monitoring unit detects that the car speed exceeds the specified value is reduced. An elevator hoisting brake device that can reduce the size of the braking device can be obtained.

1 is an overall view of a brake device for an elevator hoist according to an embodiment of the present invention. It is the elements on larger scale of the arrow E of FIG. It is a figure which shows the speed change of the elevator to which the elevator hoisting machine braking device which shows one embodiment of this invention is applied.

Embodiment 1 FIG.
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall view of a braking device for an elevator hoist according to an embodiment of the present invention. FIG. 2 is a partially enlarged view taken along arrow E in FIG. 1 and shows a state where the braking device is braked. FIG. 3 is a diagram showing the speed change of the elevator to which the elevator hoisting machine braking device according to the embodiment of the present invention is applied.

In FIG. 1, a sheave 7 is rotatably provided in the housing 5 of the hoist 1. A cage 15 is connected to one end of a rope 11 that is a suspension means wound around the sheave 7. The other end side of the rope 11 wound around the sheave 7 is also hung on the deflector 9 and a weight 17 is connected thereto. Further, as the braking device 3 of the hoisting machine 1, a disc-like brake disc 13 is provided as a member to be braked so as to be rotatable integrally with the sheave 7, and the outer edge of the brake disc 13 can be braked and released. The housing 5 is provided with a braking portion 20 as a first braking means and a braking portion 40 as a second braking means. Further, a car speed monitoring unit 50 as speed monitoring means is connected to the hoist 1.

The hoisting machine 1 is provided with a tachometer 8 that detects the rotational speed of the sheave 7, and the detected rotational speed of the sheave 7 is sent to the car speed monitoring unit 50. The car speed monitoring unit 50 calculates and monitors the speed of the car 15 from the number of revolutions of the sheave 7, and detects that the speed of the car 15 exceeds a predetermined speed upper limit value s2 as a prescribed value. A braking signal is sent to 20 and the braking part 40, the rotation of the brake disc 13 and the sheave 7 is braked, and the car 15 is stopped.

In FIG. 2, the edge on the outer peripheral side of the brake disc 13 is inserted into a groove 21 a of the body 21 having a substantially concave shape of the braking portion 20. A pair of drive friction portions 22 and 22 are provided on the groove inner walls 21b and 21b facing each other with the brake disk 13 interposed therebetween. In the drive friction part 22, a fixed iron core 31 is attached to the groove inner wall 21b, and a movable iron core 27 as a first movable iron core is provided on the brake disk 13 side of the fixed iron core 31 so as to be able to advance and retreat to the brake disk 13 side. .

An electromagnetic coil 33 is embedded in a portion of the fixed iron core 31 facing the movable iron core 27, and the fixed iron core 31 and the electromagnetic coil 33 constitute a first electromagnet. In addition, a hole 31 a for inserting a spring 29 as a first elastic member for urging the movable core 27 toward the brake disk 13 is provided in a portion of the fixed core 31 facing the movable core 27. The spring 29 has a proximal end inserted into the hole 31 a and a distal end abutted against the movable iron core 27. When a current is supplied to the electromagnetic coil 33 from a power source (not shown) and the electromagnetic coil 33 is excited, the movable iron core 27 moves toward the electromagnetic coil 33 against the biasing force of the spring 29 as the first braking force. The suction is brought into contact with the fixed iron core 31. When the current is cut off, the electromagnetic coil 33 is demagnetized and the attractive force is weakened, and the movable iron core 27 is urged away from the fixed iron core 31 toward the brake disk 13 by the urging force of the spring 29.

A friction material 23 as a first friction material is attached to the movable iron core 27 via a shoe 25 so as to face the brake disk 13. As the movable iron core 27 is urged toward the brake disk 13 by the spring 29 or is attracted to the electromagnetic coil 33 side that is excited against the urging force of the spring 29 and is brought into contact with the fixed iron core 31, The friction material 23 is pressed against or pulled away from the brake disk 13.

The braking unit 40 is configured in the same manner as the braking unit 20. The outer peripheral edge of the brake disc 13 is inserted into a groove 41 a of the body 41 having a substantially concave shape of the braking portion 40. A pair of drive friction portions 42, 42 are provided on the groove inner walls 41b, 41b facing each other with the brake disk 13 interposed therebetween. In the driving friction part 42, a fixed iron core 51 is attached to the groove inner wall 41b, and a movable iron core 47 as a second movable iron core is provided on the brake disk 13 side of the fixed iron core 51 so as to be able to advance and retreat to the brake disk 13 side. .

An electromagnetic coil 53 is embedded in the portion of the fixed iron core 51 facing the movable iron core 47, and the fixed iron core 51 and the electromagnetic coil 53 constitute a second electromagnet. Further, a hole 51 a for inserting a spring 49 as a second elastic member for urging the movable iron core 47 toward the brake disk 13 is provided in a portion of the fixed iron core 51 facing the movable iron core 47. The spring 49 has a proximal end inserted into the hole 51 a and a distal end abutted against the movable iron core 47. When a current is supplied to the electromagnetic coil 53 from a power source (not shown) and the electromagnetic coil 53 is excited, the movable iron core 47 moves toward the electromagnetic coil 53 against the biasing force of the spring 49 as a second braking force. It is sucked and comes into contact with the fixed iron core 51. When the current is interrupted, the electromagnetic coil 53 is demagnetized and the attractive force is weakened, and the movable iron core 47 is separated from the fixed iron core 51 and biased toward the brake disk 13 by the biasing force of the spring 49.

A friction material 43 as a second friction material is attached to the movable iron core 47 via a shoe 45 so as to face the brake disk 13. As the movable iron core 47 is urged toward the brake disk 13 by the spring 49 or is attracted to the electromagnetic coil 53 side that is excited against the urging force of the spring 49, the movable iron core 47 is brought into contact with the fixed iron core 51. The friction material 43 is pressed against or pulled away from the brake disk 13. When the friction material 23 and the friction material 43 are pressed against the brake disc 13, the brake disc 13 is braked. When the friction material 23 and the friction material 43 are separated from the brake disc 13, the brake disc 13 is released and can rotate.

The parts constituting the brake part 20 and the brake part 40 correspondingly, such as the friction material 23 and the friction material 43, and the fixed iron core 31 and the fixed iron core 51, are made of the same material. The braking force of the braking unit 20 as the first braking force and the braking force of the braking unit 40 as the second braking force are such that the speed of the car 15 exceeds the speed upper limit value s2 due to both braking forces. The car 15 is set to such a size that the car 15 can be stopped within a predetermined distance from the position of the car 15 when the car speed monitoring unit 50 detects that.

The magnitudes of these braking forces are determined by the friction coefficient, the pressing force, and the distance from the rotation center to the pressing position. That is, the friction coefficient between the brake disc 13 and the friction material 23 and the friction material 43, the spring 29 that presses the friction material 23 and the friction material 43 against the brake disc 13, the urging force of the spring 49, and the friction from the rotation center of the brake disc 13, respectively. It is determined by the distance to the position where the material 23 and the friction material 43 are pressed. Of these, the friction material 23 and the friction material 43 are made of the same material and have the same friction coefficient. The distance from the rotation center to the pressing position is also the same. Therefore, the magnitude of the braking force is changed by the urging force of the springs 29 and 49. The urging force of the spring 29 is set to be smaller than the urging force of the spring 49 so that the braking force of the braking unit 20 is smaller than the braking force of the braking unit 40.

Further, since the biasing force of the spring 29 is set smaller than the biasing force of the spring 49, the suction force of the fixed iron core 31 can be set smaller than the suction force of the fixed iron core 51. For this reason, the time for which the fixed iron core 31 part is demagnetized can be set shorter than the time for which the fixed iron core 51 part is demagnetized. Thus, when the braking unit 20 and the braking unit 40 receive a braking signal, the current supplied to the electromagnetic coil 33 and the electromagnetic coil 53 is cut off, and the fixed iron core 31 part is shorter than the fixed iron core 51 part. With demagnetization, the attraction is weakened. Then, the braking unit 20 starts braking first, and then the braking unit 40 where the suction force of the fixed iron core 51 part weakens starts braking.

The operation of the elevator hoisting machine braking device configured as described above will be described. In FIG. 3, for example, a change in the speed of the car 15 when the car 15 moving up or down at the speed s1 exceeds a predetermined speed upper limit value s2 for some reason is indicated by a graph line c. When the car speed monitoring unit 50 detects that the car 15 exceeds the speed upper limit s2 at time t1, the car speed monitoring unit 50 sends a braking signal to the braking unit 20 and the braking unit 40. In the braking unit 20 and the braking unit 40 that have received the braking signal, the braking unit 20 starts braking first, and then the braking unit 40 starts braking.

That is, first, at time t2 after time p1 has elapsed from time t1, the braking member 20 presses the friction material 23 against the brake disk 13 to start braking, and the speed of the car 15 is suppressed. Next, braking is started by pressing the friction material 43 against the brake disc 13 in the braking unit 40 at time t3 after time p2 has elapsed from time t1. The relationship between the times p1 and p2 is p1 <p2. Then, the car 15 is stopped by the braking unit 20 and the braking unit 40 within a predetermined distance from the position of the car 15 at the time t1 when it is detected that the speed upper limit value s2 is exceeded.

As described above, the car 15 is moved by the braking unit 20 and the braking unit 40 within a predetermined distance from the position of the car 15 at the time when the car speed monitoring unit 50 detects that the speed of the car 15 exceeds the speed upper limit s2. In stopping the vehicle, the braking unit 20 first suppresses the speed of the car 15, so that the traveling distance of the car can be shortened until both braking parts of the braking part 20 and the braking part 40 start braking. That is, among the predetermined distances for stopping the car 15, the idle running distance where the braking force does not work is shortened, and the braking distance where the braking force works is lengthened, so that the necessary braking force is reduced. Can be downsized.

For comparison with the present embodiment, for example, a change in the speed of the car in the case of braking by a braking device including one braking unit is indicated by a graph line d in FIG. When the car speed monitoring unit detects at time t1 that the car that has risen or lowered at the speed s1 exceeds the speed upper limit value s2, the car speed monitoring unit sends a braking signal to the braking unit. Since braking is performed by one braking unit, the braking force of the braking unit needs to be larger than the braking force of each of the braking unit 20 and the braking unit 40, and the urging force of the spring and the suction force of the fixed iron core are It is necessary to make it larger than the portion 20 and the braking portion 40.

For this reason, it takes longer than the braking unit 40 to stop the current to the electromagnetic coil and demagnetize it, and the attraction force of the fixed core part becomes weaker, so that the time after the time p3 has elapsed from the time t1. t4. The relationship between the times p1, p2, and p3 is p1 <p2 <p3. That is, as compared with the present embodiment, the idle running distance is increased and the braking distance is shortened among the predetermined distances for stopping the car, so that the required braking force is increased, and thus the braking device is increased in size. .

Even if the magnitude of the urging force of the spring 29 of the braking unit 20 in the present embodiment is set to the magnitude of the urging force necessary to hold the car 15 stationary at the time of stopping during normal elevator operation. good. In this case, even the braking unit 40 having a braking force larger than that of the braking unit 20 can be held stationary. As a result, when a plurality of braking parts are provided to improve the reliability of the elevator hoisting machine braking device, a plurality of braking parts 20 and braking parts 40 can be used.

In the present embodiment, the disk-like brake disc 13 is described as the member to be braked. However, the same effect can be obtained even when a cylindrical brake drum is used as the member to be braked.
Further, in the present embodiment, the description has been given in the case of a braking device provided with two electromagnetic coils and two fixed iron cores in each braking unit. The same effect can be obtained with other numbers of fixed iron cores.

Further, in the present embodiment, the parts constituting the braking unit 20 and the braking unit 40 are made of the same material, and the braking unit 20 is produced by the time difference in which the fixed core 31 and the fixed core 51 are demagnetized. In the above description, the braking start time of the braking unit 40 is changed. However, if the magnitude relationship between the braking forces of the braking unit 20 and the braking unit 40, the relationship between the respective braking start times, and the magnitude of the total braking force of both braking units satisfy the same conditions as in the present embodiment. Even if the materials of the parts constituting the respective braking parts are not the same, and even when the braking start time changes due to a factor other than the time difference for demagnetization, the same effect as in the present embodiment can be obtained.

Further, in the present embodiment, as shown by the graph line c between times t2 and t3 in FIG. 3, when the raising / lowering of the car 15 is braked only by the braking unit 20, the car 15 is at a substantially constant speed. It explained to go up and down. However, the braking force of the braking unit 20 may be set to be larger than that in the present embodiment, and the speed of the car 15 may be reduced between the times t2 and t3. The speed of the car 15 may be increased between times t2 and t3 by setting it smaller than the form. In either case, if the brake 15 and the brake 40 are set so that the car 15 can be stopped within a predetermined distance, the same effect as the present embodiment can be obtained.

In the present embodiment, the case where the suction force by the electromagnetic coil and the fixed iron core is used to separate the friction material from the brake disk against the biasing force of the spring has been described. The friction material may be separated from the brake disk by pressure. Comparing a hydraulic device that generates a large oil pressure with a hydraulic device that generates a small oil pressure, the time required to release and extinguish the oil pressure takes more time to eliminate the large oil pressure. For this reason, the same effect as the case where the attractive force by an electromagnetic coil and a fixed iron core is used is acquired.

1 hoisting machine, 3 braking device, 7 sheave, 11 rope, 13 brake disc, 15 car, 20, 40 braking part, 23, 43 friction material, 27, 47 movable iron core, 29, 49 spring, 31, 51 fixed Iron core, 33,53 electromagnetic coil,
50 Car speed monitor

Claims (3)

The speed of a car that is connected to one end of suspension means wound around a sheave rotatably provided on the hoisting machine and that moves up and down with the rotation of the sheave is monitored, and the speed exceeds a specified value. Speed monitoring means for generating a braking signal when detecting
A first braking means provided on the hoisting machine and having a first braking force for receiving the braking signal and suppressing the speed;
A second braking means provided on the hoisting machine and having a second braking force for braking the lifting when receiving the braking signal;
The first braking force is smaller than the second braking force, the first braking means starts braking earlier than the second braking means, and the first braking force, the second braking force, The elevator hoisting machine braking device, wherein the car is stopped within a predetermined distance from the position of the car at the time of detection. A braked member that rotates integrally with the sheave is provided,
The first braking means includes a first friction material provided so as to be able to contact and separate from the braked member, a first movable iron core provided so as to be displaceable integrally with the first friction material, A first elastic member for urging the first friction material and the first movable iron core toward the member to be braked; and a magnetism that can be excited and demagnetized and resists the urging force of the first elastic member. A first electromagnet capable of attracting the first movable iron core so that the first friction material is pulled away from the braked member;
The second braking means includes a second friction material provided so as to be able to contact and separate from the member to be braked, a second movable iron core provided so as to be displaceable integrally with the second friction material, A second elastic member for urging the second friction material and the second movable iron core toward the member to be braked; and an excitation and demagnetization function and against the urging force of the second elastic member. A second electromagnet capable of attracting the second movable iron core so that the second friction material is separated from the braked member;
By making the urging force of the first elastic member smaller than the urging force of the second elastic member, the first braking force becomes smaller than the second braking force,
The first braking means starts braking earlier than the second braking means by making the time for demagnetizing the first electromagnet shorter than the time for demagnetizing the second electromagnet. The brake device for elevator hoists according to claim 1. The elevator hoisting machine braking device according to claim 1 or 2, wherein the car is held stationary by the first braking force.

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