RU43682U1 - SPRING ACTUATOR - Google Patents

Abstract

The utility model relates to the field of electrical engineering, in particular to spring drives for high voltage circuit breakers. Spring drives with motor or manual winding of springs are designed for remote and local control of high-voltage switches equipped with disconnecting springs. The drives provide the dynamic switching of the circuit breaker, keeping it in the on position and turning it off, more precisely, releasing the moving parts of the circuit breaker to disconnect it with its own springs. The proposed spring drive has higher reliability, speed during shutdown, stability of its own shutdown time, ease of maintenance. This is achieved thanks to the new drive mechanism of signal contacts, automation of the cabinet heating device, uncontrolled “anti-condensation” heating device, convenience of adjusting the switching moment of the contacts used in the control circuits made on the basis of the BKM contact nodes (momentary switching interlock contact). The spring drive, placed in a cabinet with an increased width and a bottom hatch, contains working springs, control devices for turning on and off the switch, a power switching mechanism with a lever and an axis, supplemented with slots for transmitting torque, a trip buffer, a heating device with a resistor acting as an anti-condensation heating and the control panel of the operation of the heating elements, the drive mechanism of the signal contacts, signaling and locking devices.

Description

The utility model relates to the field of electrical engineering, in particular to spring drives of high voltage circuit breakers.

Known spring drive high voltage switch load (RU No. 2130212 from 05/10/1999, application No. 96115647 from 07/26/1996 N 01 N 33/76), made in the form of "spanning" through the zero position of the springs connecting the drive element in the form of a two-armed tubular lever and a driven element in the form of a shaft with a radial stop, between which there is a relative free movement, and a universal multi-position control mechanism.

The disadvantages of this technical solution include the lack of remote control of high-voltage switches, the switch is turned on by springs that are manually wound up, the duration of the shutdown process due to the sequential disconnection of the springs through the lever and traction, due to the opening of the main and arcing contacts.

The closest analogue adopted for the prototype is a spring drive (Afanasyev V.V., Yakunin E.N. Drives to high voltage circuit breakers and disconnectors. - L.: Energoatomizdat. Leningrad branch, 1982. - p. 214) .

The drive includes working springs, a spring plant mechanism, a power on mechanism, on and off control devices, a heating device.

The drive is attached to the frame of the circuit breaker; it is intended only to turn on the circuit breaker. The circuit breaker is tripped by the energy of the tripping springs located in the mechanism of the circuit breaker itself and activated when it is turned on. Factory working springs drive is produced

by electric motor or manually by turning the handle worn on the shaft end. The factory operating spring time does not exceed 15 s. The drive is designed to perform only one switching operation with fully wound working springs without their winding.

The disadvantages of this technical solution include the fact that the drive is designed to perform only one switching operation with fully wound working springs without their winding, the absence of a shutdown buffer, the duration of the shutdown process.

The task to which the proposed technical solution is directed is to create a spring drive with higher reliability, speed during shutdown, and stability of its own shutdown time.

This is achieved thanks to the new drive mechanism of signal contacts, automatic heating of the drive cabinet, the presence of uncontrolled "anti-condensate" heating, the convenience of adjusting the switching moment of the contacts used in the control circuits made on the basis of BKM contact nodes (momentary switching interlock contact). Maintenance of the drive is facilitated by the increased cabinet width and the presence of a bottom hatch.

The proposed spring drive has a slightly increased potential energy. The drive dynamically closes the circuit breaker, holds it in the on position and trips, more precisely, releases the moving parts of the circuit breaker to trip it with its own springs. In addition, the drive allows you to slowly operate the contacts of the switch (turn it on and off without any additional devices) during its adjustment or verification of operation.

The drives are manufactured in climatic versions and are designed to operate in the conditions for which the switches controlled by them are designed.

Description of the drive and its components

The drive is a separate unit adapted for attachment to a vertical wall. The figure 1 presents the kinematic diagram of the spring drive, in figure 2 - its General view. The drive consists of the drive itself and the cabinet 16 in which it is located.

Actually the drive (Fig. 2) includes the following main structural and functional units: plate 44. body 9 of the mechanism, springs 46 working, mechanism 52 of the spring plant, mechanism (power) of inclusion, control device of inclusion 54 and disconnection 55, device 56 automatic shutdown of the electric motor, buffer 5 for extinguishing the excess energy of the switching springs - the "on" buffer, signal contacts with their drive mechanism 20, panel 15 for automatically controlling the operation of the main heating and signaling a dangerous temperature drop in cabinet, terminal blocks for electrical circuits of the drive, as well as locking devices 62.

Unlike the prototype, the proposed drive has a buffer 53 for damping the kinetic energy of the moving parts of the circuit breaker during a trip (trip buffer).

The carrier plate 44 is the drive element itself, connecting it to the cabinet 16, and also serves as the basis for the installation of some elements - terminal blocks, automatic control panel for the main heating, grounding bolts. In the upper part of the plate there is an opening designed for traction connecting the drive and switch mechanisms.

The housing 9 of the mechanism is the basis of the drive. All other components of the drive itself are based on it, and through it the drive is mounted to the circuit breaker.

The body consists of two parallel plate-cheeks, welded together (via spacers) and with a third plate (base).

Working springs 46 or, more precisely, including the drive springs - this is its energy source. They accumulate energy transmitted in the process of switching on to a controlled circuit breaker.

The upper spring holders are rocker arms adapted for connecting (by means of tension bolts) of the movable upper beam 10 with springs. The lower spring holders 47 are stamped plates with elements for connecting the working springs to the lower traverse 49, connected by stops 43 and earrings 42 to the cheeks of the housing 9. The lower traverse is stationary during operation.

The mechanism of the spring plant consists of an electric motor 45, a worm gear 2, a chain gear 1, a cam 40 and a lever 7. The mechanism is equipped with a spring status indicator 11, actuated by the upper traverse of the working springs, rigidly connected to the lever 7.

The chain drive includes a drive sprocket, a driven sprocket 41 with a rotation direction arrow applied on it when the springs are wound, and a sleeve-roller chain connecting them. The driven sprocket 41 is rigidly connected to the shaft 39, on which the fist 40 is mounted (also rigidly). The shaft is supported by two ball bearings mounted in the cheeks of the mechanism housing.

The lever 7 applies both to the mechanism of the plant of springs, and to the power mechanism of inclusion. Its base is made up of two parallel cheeks, welded together with the help of several spacers. The lever is three-shouldered. A roller 35 is mounted on its shortest shoulder, which interacts with the fist of the spring plant, and in the cheeks of the longest shoulder there are holes for installing the upper beam. On the same shoulder there is a roller 6 interacting with the “on” buffer, designed to reduce radial loads on the buffer rod, and a spring-loaded tooth 8 — for fixing the lever in a position corresponding to the charged state of the springs. On the third shoulder

the clutch lever 31 is installed. The lever 7 is mounted on the axis 34 by means of two ball bearings, and the axis itself (also on the bearings) is installed in the cheeks of the mechanism housing.

The power switching mechanism is placed between the cheeks of the housing.

Its purpose is to transfer the force of the working springs of the drive (when turned on) to the circuit breaker mechanism, to coordinate the power characteristics of the springs with the resistance forces to turn on the circuit breaker, as well as to enable the circuit breaker to be able to turn off without interruption at any time after it is fully turned on.

The mechanism consists of the leading lever 7, the lever-clutch 31, the driven lever 19, the earring 28, and the elements that determine the angle of rotation of the driven lever (or the stroke of the earring) that has already been partially described above.

The axis of the clutch lever 31 is mounted in the plain bearings. The purpose of the clutch lever is to provide one-way communication between the master lever and the follower in the process of turning on the switch.

Driven lever 19 - two shoulders, cast, representing two parallel cheeks connected by two jumpers. A lever is placed between the cheeks of the driving lever 7 and mounted on the axis of the latter.

In contrast to the prototype, where the lever hole and axis are made smooth, in the proposed drive, these elements have splines for transmitting torque from the driven lever - the axis 34 itself (acting here as a shaft) and then to the lever that ultimately transfers the rod movement Piston off buffer.

The power control device (block) is installed in the upper part of the mechanism case opposite the front cabinet door.

The purpose of the device is to fix the drive lever 7 in the position corresponding to the charged state of the springs, and release it to perform the operation of turning on the switch.

The device consists of an electromagnet (EV) YA2 installed with a vertical axis of the core

on a special bracket, dogs 13 and the "intermediate" lever 18.

In addition, the electromagnet has a button for manually turning on the drive.

The electromagnet coil is single-section, it consists of a frame made of thermosetting insulating material, and a winding, the ends of which are displayed on terminal clamps mounted on the bracket.

The trip control device is installed in the front upper part of the mechanism housing, under the roof hatch of the drive cabinet.

This drive arrangement is fundamentally different from the inclusion control device. In order to improve performance when performing the operation of opening the circuit breaker without increasing the power consumption of the electromagnets YA1, UA3, the third stage of reducing the force acting on the side of the drive power mechanism (or the breaking spring of the circuit breaker) on the dog 21, interacting with the disconnecting electromagnet, was introduced into the device. For this, the working (cylindrical) surface of the short arm of the dog is made eccentric relative to the axis of its rotation. As a result, under the action of the force coming from the disconnecting spring of the switch, the dog tends to turn clockwise. This is prevented by an additional spring-loaded dog 61, which can be affected by either of the two disconnecting electromagnets (upon receipt of a command to turn off the device), as well as the handle of the local circuit breaker ..

The device automatically turns off the motor when the preparation of the drive to turn on.

The device is located in the lower front of the right cheek of the mechanism housing. The following elements are included in it: finger 48, mounted on the fist 40 of the spring plant; lever spring 50, spring-loaded by its own spring, mounted on the roller with the possibility of rotation relative to it

only at a certain angle; a cam 4 rigidly sitting on the roller with a spring returning the roller to its original position after removing the influence of the lever 50 of the finger 48, and the contact assembly BKM (locking contact of moment switching) with the NC contacts SQ2 interacting with the cam 4.

The “on” buffer is installed in front of the mechanism body, directly behind the control panel. The buffer body is inserted into the jumper hole between the cheeks. The buffer is hydraulic.

Shutdown buffer 53 (also hydraulic) is available only in the proposed drive, unlike the prototype. It is mounted on the right side of the mechanism case, at its base, on an axis passing through both cheeks of the case, and can be rotated on it within certain limits.

The buffer is designed to quench the kinetic energy of the moving parts of the switch at the end of the stroke of its contacts in the direction of disconnection.

The connection of the buffer rod with the driven lever of the drive is carried out by means of a splined shaft, the levers - the master and the slave.

The device for locking the electric motor when the handle of the manual winding is installed on the input shaft of the gearbox consists of the hub of the handle 3 itself; a limit switch mounted on the gearbox housing, the opening contacts SQ1 of which are located in the power supply circuit of the motor starter coil KM1; strips between the hub and the pusher of the switch, excluding jamming of the latter.

The blocking of the command to turn on when the circuit breaker is turned on, as protection against improper operator actions and protection against combustion of the EV coil, is provided by interrupting the power supply circuit when the circuit breaker is turned on, for which the disconnecting (closed when the circuit breaker is open) contacts SA3 of the BKM contact node controlled cam 22), rigidly connected to the roller 24, driven from the driven lever 19 of the drive through the wings 17. The mentioned contact node in the block with two (or three) BKM is placed

on the right cheek of the mechanism case, at its upper edge.

The blocking of the command to trip when the circuit breaker is off is similar in purpose and is provided by the same elements as described above, with the only difference being that it uses the closing (open when the circuit breaker is open) contacts SA2 of the BKM contact node included in the blocking unit giving a command to turn on when the switch is off.

The signaling about the position of the contacts of the controlled switch (more precisely, about the position of the output element of the drive) is electric, it is carried out using contacts SA1 and SA7. SA1 is a block of signal contacts of a rotary type with 12 circuits (type KSA-12), and SA7 is a block of contacts with 8 circuits (type KSA-8). Both contact blocks are mounted on the left cheek of the mechanism housing. The rotary shaft of the KSA-12 unit is driven from the drive shaft 24 by means of a lever 20, a rod 57 of adjustable length and a lever 58. The KSA-8 shaft is driven from the latter by a rod 60 and a lever 59.

Signaling of a dangerous temperature drop in the drive cabinet is carried out using a thermal relay mounted on panel 15, the contacts of which are closed when the temperature in the cabinet drops below minus 18 ± 2 ° С.

The drive heating device consists of a 50 W resistor 37 placed in the cabinet, acting as anti-condensate heating (which remains in the on position when the circuit breaker is turned on) and two main heating units 51, each of which contains two 400 W tubular electric heaters (TEN) .

The drive heating device also includes a panel 15 installed in the lower part of the plate with devices for automatically controlling the operation of the heating elements (temperature sensors and a starter).

Automatic inclusion of the main heating is provided when

temperature in the drive cabinet (1 ± 1) ° С, shutdown at a temperature (8 ± 2) ° С.

In tropical drives, only anti-condensation heating is installed - the mentioned resistor.

The drive cabinet 16 serves to protect its elements from solar radiation and atmospheric influences. The cabinet is attached to the base plate 44. The roof of the cabinet has a hatch. To facilitate maintenance of the drive, the cabinet is made with an increased width, and a hatch is also made in the bottom of the cabinet, closed by a lid located inside the cabinet.

Drive operation

The operation of the drive as a whole is illustrated by the kinematic (figure 1) scheme.

The work can be divided into three main stages:

- factory of working springs;

- inclusion of the switch;

- shutdown.

Spring plant

The drive spring plant can be performed in three ways:

a) manually;

b) using a manually controlled electric motor;

c) an electric motor operating in automatic mode. Manual springs are charged, as a rule, in the absence of electric power to the electric motor, for example, when preparing the drive for the first time the circuit breaker is switched on at a substation (dead end), the auxiliary transformer of which is powered from a line controlled by the same circuit breaker. The plant is carried out by rotating the worm shaft of the gearbox 2 with the handle 3 in a clockwise direction. The shaft must be rotated until the contact block SQ2-SH2- is switched

SA5, i.e. until the fist reaches position 40 in which he will not interfere. inclusion.

The spring plant with the help of a manually controlled electric motor is most often used in adjustment work and repair.

Automatic winding of springs takes place during normal operation of the drive during the overhaul period. The spring factory electric motor is turned on at the beginning of the process of turning on the controlled switch when the crosshead 10 is lowered so that the contacts of the SQ3-SA6-SH4 block controlled by the cam part of the spring status indicator lever 11 switch to the initial position.

In this case, the contacts SQ3 will close, which will provide voltage to the KM1 starter coil and, therefore, to the motor windings. The rotation of the engine rotor through gearbox 2 and the chain drive will be transmitted to the fist, but the fist will not be able to prevent turning on, since it will end before the working surface of the fist comes into contact with the roller 35 of the drive lever.

As soon as the working surface of the fist comes into contact with the roller (with any method of winding the springs) - the working springs 46 will start cocking, because the distance between traverses 49 and 10 will begin to increase. At a certain moment, the clutch lever 31 will meet the L-shaped emphasis 36, which will translate it into working position (will bring the working surface of the clutch lever under the roller 33 of the driven lever 19). Toggle springs 32 will lock the clutch lever in this position relative to the driving lever 7.

At the same time, the tooth 8 of the driving lever meets the retaining axis of the lever 18 and, under its influence, turns counterclockwise, without hindering the rotation of the lever 7. Upon transition beyond the axis, the tooth 8 will return to its original position under the action of its spring. At the moment the contact line of the roller 35 with the fist 40 reaches the highest point of the profile of the latter (R = 130 mm), the rotation of the lever 7 is reversed. With a further rotation of the fist 40, the tooth 8 will rest against the holding axis of the lever 18, which will fix the lever 7 in

11 position corresponding to the charged state of the springs.

It should be noted that even before the full spring plant, the upper crosshead 10 will meet the pointer lever 11 and by the end of the plant will turn it so that it opens the SQ3 contacts with its cam part. But the engine will continue to work, since the starter coil KM1 will be powered by a circuit containing closed contacts SQ2. The latter will open, and the motor will stop only when the fist 40 is in a position that does not prevent the circuit breaker from being turned on. In this case, the finger 48 of the fist will hold the lever 50 in the lower position, and, therefore, the contacts SQ2 will remain open, and SA5 will be closed, which will prepare the electromagnet circuit YA2 for receiving a turn-on command.

The spring factory process is complete.

Switch on

Operational closing of the circuit breaker is carried out by supplying voltage to the magnet coil YA2. Non-operational switching can be performed, moreover, by pressing the YA2 button manually. In this case, the dog 13 is knocked out from under the roller of the lever 18. The latter, having received the possibility of rotation, is deflected by the action of the tooth 8 in the clockwise direction of rotation and thereby releases the driving lever 7. The lever 7 is rotated counterclockwise by the action of the working springs 46, capturing a slave lever 19, and produces a switch.

At the beginning of the rotation of the levers in the direction of inclusion, the action of the traverse 10 on the lever-pointer 11 of the state of the springs is removed. The latter, under the action of its spring, rotates counterclockwise and removes the effect of its rear cam on the contact block SQ3-SA6-SH4. In this case, the contacts SQ3 close the KM1 starter coil circuit, ensuring that the spring factory electric motor is switched on.

When the levers 7 and 19 rotate, the roller 24 is constantly connected with the follower

lever 19 through the wings 17, rotates and switches: using cam 22 - contact block SA2-SQ4-SA3, and using lever 20 - contacts SA1 and SA7.

In the final turning zone of levers 7 and 19 in the direction of engagement, the right shoulder of the clutch lever 31 meets the bolt 30, from which the clutch lever rotates clockwise and its left shoulder comes out of contact with the roller 33. The levers 7 and 19 are disengaged. Their disengagement occurs in a position guaranteeing the retraction of the tooth 26 for the retaining axis of the lever 14.

The drive lever 7 continues to rotate counterclockwise, but after the roller 6 meets the plunger of the buffer 5, it is braked last and stops.

The driven lever 19, on which, after disengaging with the driving lever 7, the operating springs 46 of the drive do not act, after a certain inertial “run-out” stops, and then, under the action of the breaking spring of the switch, starts to rotate clockwise until its tooth 26 rests against the holding axis of the lever 14. This completes the activation process.

Unlike the prototype in the proposed drive, where the driven lever is connected via a splined shaft to the lever, the latter, turning counterclockwise when the switch is turned on, first rotates freely. Then, resting on a bolt, it also engages in rotation a lever consisting of cheeks and, therefore, drives a piston with a buffer rod.

Circuit breaker

Operational shutdown can be carried out either at the command of the operator (from the control key), or from the protection action. In this case, the voltage is supplied to the electromagnet YA1 or UA3.

The shutdown occurs as follows: when the tripping electromagnet is activated, the dog 21 turns, giving

the ability to rotate under the action of the tooth 26 and the intermediate lever 14. The latter releases the driven lever, and the disconnecting springs (spring) of the switch bring it to its original position, in which the earring 28 pivotally connected to the lever rests against the frame of the disconnect damper.

In this case, the link 17 connected to the axis of the earring 28 rotates the roller 24, and through the lever 20 and the rod 23, the signal contacts shaft SA1 so that the position of the contacts changes to inverse. At the same time, the contacts of SA7 are switched.

In contrast to the prototype, in the proposed drive, when disconnected, the spline shaft and, consequently, the lever also rotate. After turning it at a certain angle, determined by the size of the gap between the stop bolts of the lever, the latter also begins to rotate, setting the piston of the trip buffer in motion. The piston displaces the working fluid from the piston cavity into the cavity between the housing and the glass through the holes in the latter. Along the piston, the number of "working" holes and their cross-sectional area are reduced, which increases the resistance to movement of the piston and, consequently, inhibits all parts of the switch and actuator moving during shutdown. The movement stops when the earring rests in the frame of the shutdown damper.

The shutdown is complete.

Claims (6)

1. Spring drive for high-voltage circuit breakers, including a cabinet, plate, housing, working springs with the mechanism of their plant, a power switching mechanism with a lever and an axis, a trip control device, an automatic motor shutdown device, signal contacts with their drive mechanism, an automatic operation control device main heating, an alarm device about a dangerous temperature drop in the cabinet, terminal blocks for electrical terminals of the drive, locking devices, characterized in he completed off buffer, located on the right side at the base, with the drive cabinet for ease of service is provided with a bottom hatch. 2. The spring drive for high-voltage circuit breakers according to claim 1, characterized in that the third step of reducing the force acting on the drive power mechanism is introduced into the trip control device. 3. The spring drive for high-voltage switches according to claim 1, characterized in that the hole of the lever and the axis of the power mechanism are supplemented with slots for transmitting torque from the axis to the lever. 4. The spring drive for high voltage circuit breakers according to claim 1, characterized in that the drive mechanism of the signal contacts is supplemented by a rotary type signal contact block. 5. The spring drive for high-voltage switches according to claim 1, characterized in that a resistor is introduced into the automation of the heating device, which acts as anti-condensation heating. 6. The spring drive for high-voltage circuit breakers according to claim 1, characterized in that the contacts in the control circuits are made in the form of interlock contacts of moment switching.