JPH0733392A - Emergency lowering speed control device for elevator - Google Patents

Abstract

PURPOSE:To provide arm emergency lowering speed control device requiring no frequent maintenance and inspection without generating problems on quality, performance, and safety caused by heating. CONSTITUTION:A spindle member 34 is slid to the outside in the radial direction by centrifugal force along a pin 32 fixed to the second rotors 28, 29 rotated integrally with a motor. When the deflection quantity of a disk spring 36 exceeds a set value, the spring load is abruptly decreased, the spindle member 34 is brought into pressure contact with the inner periphery of a sheave main body 13, and a brake is applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency lowering speed control device for an elevating device accompanied by ascending and descending operations such as a working gondola, winch, hoist and the like.

[0002]

2. Description of the Related Art In these lifting devices, a mechanical brake has been used as a conventional method for controlling the inertial force when descending. As an example thereof, Japanese Patent Laid-Open No. 2-158
There is a mechanical brake described in Japanese Patent No. 597.
As shown in FIG. 6, this mechanical brake is a rope that moves on the rope s while winding the tow rope s around the sheave r that is rotationally driven by transmitting power from the motor a to the sheave r via the speed reducer Q. A clutch member c provided on the traction device on the output shaft b side of the motor a
A brake member e having a flange opposed to the brake flange d is provided slidably in the axial direction on the outer peripheral portion of the clutch member c, and a roller thrust bearing is interposed between the clutch member c and the rear surface of the flange f. A roller bearing is interposed between the outer peripheral portion and the outer peripheral portion. Between the brake member e and the brake flange d, a brake disc i that is axially movable along a spline h formed on the inner peripheral portion of the sheave body g is provided, and on both sides of the brake disc i, The brake lining j is attached.

A disc spring k is interposed between the rear surface of the brake member e and the sheave body g, and a brake is applied by pressing the brake disc i with the brake flange d and the brake member e. You can do it.

As a mechanism for engaging and disengaging the brake mechanism, the flanges f and m of the clutch members c and e are respectively provided with three grooves n which are long in the circumferential direction and are equally spaced around the circumference. These grooves n are formed in a V shape having a deep central portion and shallow both sides. Steel balls o are put in the grooves n as rolling elements, and the distance between the flanges f and m can be changed depending on the position of the groove n. A spring p is provided between the clutch member c and the brake member e so that the steel ball o does not come out of the groove n when the flanges f and m are opened.

[0005]

Since the above-mentioned conventional mechanical brake basically replaces the potential energy at the time of descending with the thermal energy, heat is always generated at the time of descending, so that the change of oil and fat and the brake torque are caused. Change, and changes in quality, performance and safety such as wear and breakage of the brake lining are likely to occur, and therefore, frequent maintenance and inspection of the brake is required, resulting in an increase in maintenance cost.

The present invention has been made in consideration of the problems of the above-mentioned conventional mechanical brakes, and there is no risk of quality, performance and safety problems due to heat generation such as wear and damage of the lining, and frequent maintenance. It is an object of the present invention to provide an emergency lowering speed control device for a lifting device that does not require inspection.

[0007]

The emergency lowering speed control device in the lifting device for achieving the above object of the present invention has a first space having a space inside in a radial direction in which power is transmitted from a motor through a speed reducer and rotated. A rotating body, a second rotating body disposed in the inner space of the first rotating body and fixed to the rotating shaft of the motor, and rotating integrally with the rotating shaft of the motor; A plurality of pins which are fixed to the rotating body and extend in the radial direction, a pin insertion hole having a diameter slightly larger than the outer diameter of the pin, and a disc spring accommodating recess formed outside the pin insertion hole. The second rotating body and the first rotating body slidably in the radial direction along the pin fitted in the pin insertion hole.
A plurality of weight members arranged between the inner peripheral surface of the rotating body of
It is accommodated in the disc spring accommodating recess of the weight member so as to be locked to the outer end of the pin, and the spring load increases in accordance with the increase in the deflection amount until the deflection amount reaches a set value. However, when the amount of deflection exceeds the set value, a disc spring having a characteristic that the spring load sharply decreases is provided.

[0008]

Since the weight member is configured to slide in the radial direction along the pin fixed to the second rotating body that rotates integrally with the motor, centrifugal force is increased as the rotation speed of the motor increases. When the force increases, the weight member slides radially outward along the pin due to centrifugal force and compresses the disc spring, so that the amount of deflection of the disc spring increases. The braking force is the difference between the centrifugal force and the spring load of the disc spring, but the spring load of the disc spring increases with the amount of deflection until the amount of deflection reaches the set value. It acts as a force that suppresses the increase. When the amount of flexure of the disc spring exceeds the set value while the motor speed further increases and the centrifugal force increases, the spring load sharply decreases, resulting in a sudden increase in the braking force, which is the difference between the centrifugal force and the spring load. Increased and the outer peripheral surface of the weight member is first
The brake is applied by being pressed against the inner peripheral surface of the rotating body.

Therefore, the set value of the flexure amount of the disc spring is set to a certain value which exceeds the flexure amount of the lifting device due to the rated descending speed, and an increase in the descending speed due to inertia during descending at the rated speed causes regeneration of the motor. If configured to suppress using braking, in an emergency such as when the motor power is disconnected, regenerative braking of the motor does not operate and the self-holding brake of the motor must be manually released. If the descending speed exceeds the rated speed due to an abnormal increase in speed due to inertia of the descending lifting device,
Since the amount of deflection of the disc spring exceeds the set value, the braking force is exerted, abnormal acceleration is suppressed, and the lifting device can descend at a safe descending speed close to the rated speed. When the emergency situation is released and the descending speed returns to the rated speed, the amount of flexure of the disc spring falls below the set value, so the brake is automatically released.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In this embodiment, the emergency lowering speed control device according to the present invention is applied to the rope pulling device described in Japanese Patent Laid-Open No. 158597/1990. FIG. 1 is a longitudinal sectional view of this embodiment, FIG. 2 is a front view of a main portion of the embodiment, and FIG.
Is a perspective view, FIG. 4 is a graph showing the relationship between centrifugal force and disc spring load-deflection characteristics, and FIG. 5 is a sectional view showing an example of a disc spring.

In this rope pulling device 10, the sheave 12 provided in the machine frame 11 is composed of a sheave body 13 and sheave side plates 15 and 15 attached to both sides of the sheave body 13 to form grooves of the wire rope 14. .

The sheave body 13 constitutes a first rotating body, and the tip portion thereof has a thickness slightly smaller than the diameter of the wire rope 14 and serves as a bottom portion of the groove. If necessary, knurling is applied to the outer periphery as one of the uneven processing to increase the friction coefficient. The outer circumference of the outer side of the groove of the sheave body 13 is attached to the machine frame 11 by the ball bearing 16
It is mounted so that it can be rotated through. The sheave body 13 has a space on the inner side in the radial direction in which a brake mechanism described later is arranged.

The sheave side plates 15 and 15 attached to the sheave body 13 are formed in a ring shape by using leaf springs, and are fixed by eight bolts 26 from each side.

In such a sheave 12, the wire rope 1
The rope guide 18 is provided on the machine frame 11 outside the sheave 12 in order to reliably guide the rope 4.
The tip portion of 8 is arranged so as to be inserted between the two sheave side plates 15 and 15 in a non-contact state.

Next, the drive mechanism and the brake mechanism of the sheave 12 will be described. First, a self-holding type induction motor with a brake 23 is attached to a side portion of the machine casing 11 as a drive source, and one rotating member 28 is attached to an output shaft 24 thereof via a spline. The other rotating member 29 is attached to the rotating member 28 via four pins 30 arranged at equal intervals. The rotating members 28 and 29 form a second rotating body and serve as the output shaft 2 of the motor.
It rotates together with 4. The rotary member 28 is not shown in FIGS. 2 and 3.

On the rotary member 29, four pins 32 extending in the radial direction are arranged at equal intervals and screwed. In FIG. 1, only one pin 30 and 32 are shown for convenience.

Four weight members 34 are provided between the outer peripheral surface of the rotating member 29 in which the pins 32 are planted and the inner peripheral surface of the sheave body 13.
Are evenly spaced. The weight member 34 has a pin insertion hole 34a having a diameter slightly larger than the outer diameter of the pin 32 and a disc spring accommodating recess 34b formed on the outer side in the radial direction of the pin insertion hole 34a. It is configured to be slidable in the radial direction along the pin 32 fitted in the. The weight member 34 and the sheave body 13 are formed by casting. The brake lining may be provided along the outer circumference.

The outer end portion of the pin 32 is an enlarged diameter portion 32a, and this enlarged diameter portion 32a is located in the disc spring accommodating recess 34a. A disc spring 36 is housed between the enlarged diameter portion 32 a of the pin and the bottom surface of the recess 34 a of the weight member 34. In the disc spring 36, as shown in FIG. 4, the spring load increases in accordance with the increase in the flexure amount until the flexure amount reaches a certain set value P, but when the flexure amount exceeds P, the spring load sharply increases. Designed to have decreasing properties.
The disc spring having such characteristics has, for example, an outer diameter Da = 16 mm and an inner diameter Di = 8.2 m as shown in FIG.
m, plate thickness S = 0.25 mm, total deflection h = 0.7 mm,
It can be obtained by combining three commercially available disc springs having a free height Io = 0.95 mm as illustrated. Note that the disc spring 36 and the pin 32 are not shown in FIG. 3.

As is apparent from FIGS. 2 and 3, the flange portion 29a of the rotating member 29 is formed with columnar portions 29b having a substantially triangular cross section at equal intervals in the circumferential direction so as to extend in the axial direction. Each weight member 34 includes two adjacent columnar portions 2
It is housed in the space between 9b. With this configuration, it is possible to prevent the weight member 34 from moving in the circumferential direction due to the inertia accompanying the rotation of the rotating member 29.

The input shaft 40 of the cyclone speed reducer 39 is arranged coaxially with the output shaft 24 of the motor, and the output part 41 of the cyclo speed reducer 39 is connected to the side part of the sheave body 13 of the sheave 12 with a bolt 42. Motor 2 connected together
The driving force from the motor 3 is transmitted to the sheave 12 via the rotary members 28 and 29 and the cyclone speed reducer 39.

Next, the operation of the emergency lowering speed control device will be described. The set value P of the flexure amount of the disc spring 36 is set to the flexure amount corresponding to the rated descending speed of the rope pulling device (for example, the motor rotation speed is 1700 rpm at 60 Hz as in FIG. 4).

An increase in the descending speed due to inertia during descending at the rated descending speed is suppressed by utilizing regenerative braking of the induction motor. Even if the motor used is not an induction motor, it is possible to provide a control device for returning the rated speed by servo control when the descending speed exceeds the rated speed.

Due to the inertia of the rope pulling device that descends in an emergency when the regenerative braking of the motor is not activated and the self-holding brake of the motor must be manually released when the motor power is disconnected. When the descending speed exceeds the rated speed due to an abnormal speed increase, the weight member 34 slides outward in the radial direction due to an increase in centrifugal force and compresses the disc spring 36, whereby the flexure amount of the disc spring 36 is set to the set value. Increase beyond P. Then, in FIG. 4, the spring load of the disc spring 36 decreases sharply while the centrifugal force increases,
The difference between the centrifugal force and the spring load at point Q at the set rotation speed of 1820 rpm acts as a braking force. That is, the outer peripheral surface 34 c of the weight member 34 is pressed against the inner peripheral surface of the sheave body 13, so that the sheave body 13 is braked.

As a result, when the rotation speed of the sheave 12 and the rotation speed of the motor 23 decrease, the weight member 34 slides inward in the radial direction as the centrifugal force decreases, so that the amount of deflection of the disc spring 36 decreases. When the amount of this deflection decreases to the set value P corresponding to the rated speed, the braking force sharply decreases and the weight member 34 releases the brake applied to the sheave body 13.

[0025]

As described above, according to the present invention, the emergency lowering speed control device is constituted by a centrifugal brake in place of the conventional mechanical brake, and the centrifugal brake is configured so that the amount of deflection of the disc spring is a set value. Since it was constructed using a disc spring that has a characteristic that the spring load sharply decreases when it exceeds, the set value of the deflection amount of the disc spring is set to a certain value that exceeds the deflection amount due to the rated lowering speed of the lifting device. If the regenerative braking of the motor is used to suppress the increase of the lowering speed due to the inertia when the motor is descending due to the rated speed, the regenerative braking of the motor will not operate even when the power supply of the motor is disconnected, During an emergency when the self-holding brake must be lowered with the brake released manually, the descending speed exceeded the rated speed due to an abnormal increase in speed due to the inertia of the descending lifting device. Expediently, the amount of bending of the disc spring exceeds the set value the brake force is exerted, abnormal acceleration is suppressed, the lifting device can be lowered at substantially close to the rated speed safe lowering speed.

In the speed control device of the present invention,
Since no friction portion such as the brake lining is provided, there is no possibility of causing problems in quality, performance and safety due to heat generation such as wear or damage of the friction portion, and it is not necessary to perform frequent maintenance inspections. Therefore, the maintenance cost can be significantly reduced as compared with the conventional mechanical brake.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a front view showing a main part of the embodiment.

FIG. 3 is a perspective view showing a main part of the embodiment.

FIG. 4 is a graph showing the relationship between centrifugal force and disc spring load-deflection characteristics.

FIG. 5 is a cross-sectional view showing an example of a disc spring.

FIG. 6 is a vertical sectional view showing an example of a conventional mechanical brake.

[Explanation of symbols]

 13 sheave body (first rotating body) 23 motor 28, 29 rotating member (second rotating body) 32 pin 34 weight member 34a pin insertion hole 34b disc spring accommodation recess 36 disc spring

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[Procedure amendment]

[Submission date] August 11, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

In the speed control device of the present invention,
Since no friction portion such as the brake lining is provided, there is no possibility of causing problems in quality, performance and safety due to heat generation such as wear and damage of the friction portion, and it is not necessary to perform frequent maintenance inspections. Therefore, the maintenance cost can be significantly reduced compared to the conventional mechanical brake. In the speed control device of the present invention, the motor
Directly connected second rotating body and first to apply brake
Along the pin fixed to the second rotating body between the rotating body
There is only a weight member that slides along the first rotating body.
When applying a brake to the
It slides radially outward and its outer peripheral surface is the inner periphery of the first rotating body.
The brake can be applied only by being pressed against the surface.
Install another middle trunk member between the weight member and the first rotating body.
It has the advantage of not requiring it.

Claims (1)

[Claims] 1. A first rotating body having a space on the inner side in the radial direction in which power is transmitted from a motor via a speed reducer to rotate, and rotation of the motor arranged in an inner space of the first rotating body. A second rotating body fixed to the shaft and rotating integrally with the rotating shaft of the motor; a plurality of pins fixed to the second rotating body and extending in the radial direction; A pin insertion hole having a slightly larger diameter and a disc spring accommodation recess formed outside the pin insertion hole are provided, and the pin insertion hole slides radially along the pin fitted into the pin insertion hole. A plurality of weight members that are arranged between the second rotating body and the inner peripheral surface of the first rotating body as much as possible, and the weight members that are locked to the outer ends of the pins. The disc spring is accommodated in the recess for accommodating the disc spring, and the spring load increases in accordance with the increase in the deflection amount until the deflection amount reaches the set value. Pressurized Suruga deflection of emergency descent speed control device in the lifting device, characterized in that it comprises a disc spring having a characteristic spring load decreases abruptly exceeds set value.