WO2019004876A1

WO2019004876A1 - Safety device

Info

Publication number: WO2019004876A1
Application number: PCT/RU2018/050066
Authority: WO
Inventors: Алексей Анатольевич ТОКАРЕВ; Иван Павлович ЛАВРОВ; Игорь Николаевич МАРЧЕНКО
Priority date: 2017-06-29
Filing date: 2018-06-27
Publication date: 2019-01-03
Also published as: RU2649661C1; GEP20217278B; EA036803B1; MD4836C1; MD20200005A2; MD4836B1; EA202090171A1

Abstract

The invention is used for protecting a transformer against short-circuiting and overloads in the primary winding. The invention makes it possible to achieve a simplification of the design, the absence of a reaction to current changes caused by voltage surges, to eliminate unwarranted cutting off of a consumer, to produce information about actuation of the device, and to increase safety. A device comprises a housing (1) in the form of a tube with contact caps (2, 3), an electromagnetic tripping mechanism (4), a unit (5) for controlling the tripping mechanism, a trip-free release mechanism (6) and an actuation indicator (7). The electromagnetic tripping mechanism (4) comprises a magnetic conductor (8), and an inductance coil (9) with a magnetic core (10) and an armature (11). The unit (5) for controlling the tripping mechanism comprises a resettable fuse (12) and a variable resistor (13) which are connected in parallel. The trip-free release mechanism (6) comprises a guide element (15), a bushing (16), an opening spring (17), a damping spring (18) and a monofilament thread (19).

Description

Safety device

The invention relates to the field of electrical engineering and can be used in electrical installations with a voltage class up to 20 kV to protect a single-phase power or instrument transformer from a short circuit in the secondary circuit of a transformer, as well as from overloads in the primary winding of a transformer at rated protection actuation current from 0, 3 A.

The most common device used to protect an electrical circuit from overvoltage is a fuse. In accordance with GOST 2213079, a fuse is a switching electric device designed to disconnect a protected circuit by destroying specially-designed current-carrying parts under the action of a current exceeding a certain value, followed by extinguishing the arcing that occurs during . authors.)

The classic design has a high-voltage fuse that contains a cartridge in the form of an insulating tube with contact caps, inside which one or several fusible inserts are placed, which are fixed with the possibility of replacement. Inside the cartridge is placed the trigger indicator, which is pushed out when the fuse is tripped (RF patent, PTL: RU152790, H01H 85/055, H01C 7/12, 06.20.2015).

In the event of an overcurrent with the frequency of the network, which leads to the operation of the fuse, the gap of the low-melting conductor is the only section of the discontinuity, which leads to the precise operation of the fuse. In this case, the fuse loses performance. However, in a surge overvoltage mode, a low-melting fuse conductor can have a wide variety of damage that can lead to different effects, ranging from separating several parallel narrow sections to general destruction of the low-melting conductor without high-impedance breaking. Impulse currents often lead to a substantial mechanical load of the low-melting conductor and to very different current distribution in the areas of the low-melting conductor. Thus, in fuses with a fusible insert, due to the presence of a response to impulse overvoltages, partial melting of a low-melting conductor is possible, in which the molten remains of a low-melting conductor and the surrounding aggregate lead to the preservation of a conductive connection with a resistance of several kΩ. This, in the event of a new overvoltage, can cause significant damage. In addition, due to defective overvoltage protection, a consumer is exposed to danger (RF patent PTL: RU240127, H01H 85/30, 07.20.2010).

Thus, there is the problem of creating a compact safety device, which excludes the possibility of its operation due to an accidental short-term peak current overload or over-current overload caused by a surge voltage.

Known safety devices based on the use of electromagnetic releasers.

In accordance with GOST R 50343-99, a release is a device mechanically connected to an electrical switch (or embedded in it) that releases a holding device in the mechanism of a circuit breaker and causes the switch to automatically trip at a given current response.

Such safety devices include an electromagnetic release and a free release mechanism. The release, controls the specified current value of the protected circuit and acts on the mechanism of free tripping, disconnecting the power supply network, if a short circuit or overvoltage occurs in the protected circuit. After actuation, the safety device with magnetic release is reset. At the same time, the device maintains its performance after operation (http://allrefrs.ru/4-17276.html; https://electric-220.ru/news/tok_rascepitelja_avtomaticheskogo_vykljuchatelja/2014-04-22-587)

A safety device (see ibid.) Is known, which contains a flat case in which a direct current electromagnetic release device and a free release mechanism are placed. Electromagnetic release is a solenoid with a spring-loaded core, which is connected with a moving power contact. Electrically, the coil of the solenoid is connected in series to the power circuit by means of leads extending outside the housing.

The mechanism of free tripping is made in the form of a system of hinged-connected levers connecting the on and off buttons of the switch with a moving contact node.

In normal operation, a current flows through the solenoid coil, at which the magnetic flux is small to initiate the movement of the moving core. The power contacts are closed, which ensures the normal operation of the protected installation. During a short circuit, a sharp increase in the current in the solenoid leads to a proportional increase in the magnetic flux, able to overcome the action of the spring and move the core and the associated moving contact acting on the free tripping mechanism, which leads to de-energizing the protected line.

Closest to the proposed is a safety device, containing, placed in a flat case, an electromagnetic direct current release and a mechanism for free tripping. The electromagnetic release contains a magnetic core with a magnetizing winding located on the frame, an anchor interacting with a moving pusher that is spring-loaded relative to the magnetic core and acts on the rail of the free tripping mechanism. The release contains an output terminal and a terminal with which it is electrically connected to the wire of a three-phase electric circuit. The magnetic core of the inductor is made of upper and lower parts.

The mechanism of free tripping is designed as a system of pivotally connected levers connecting the on and off buttons of the switch. The actuation is fixed by the extended power button, which corresponds to the de-energized state of the release. (RF patent PTL: RU78985, H01H 73/36, 10.12.2008, FIG. 2).

The advantage of the above described safety devices is to maintain operability after operation. However, in known safety devices they use a direct current electromagnetic release device, as a result of which, in known safety devices, there is no selectivity in response to a change in the value of the monitored current. This is explained as follows. In accordance with GOST R 50345-99, a direct current electromagnetic release device is a release device that is triggered when a current exceeds a specified value, and that is triggered by a current flowing directly in the controlled circuit. Considering the fact that electromagnetic releases have a very high speed (up to hundredths of a second), a safety device with a direct current electromagnetic release reacts to pulsed overvoltages and even to an occasional short-term increase in current in a controlled circuit. This leads to unreasonable shutdown of the consumer.

The use of the button in the known safety devices as a trigger for switching on in the extended state is not reliably informative, which does not exclude the possibility of re-enabling the safety device and creating an emergency. As a result, the safety of identified known safety devices for the consumer is reduced.

In the known safety devices, the free-decoupling mechanism is a system of pivotally connected levers, which complicates it. In addition, to actuate a system of pivotally connected levers, the reciprocating movement of the movable core of the inductor is converted into rotational movement of the levers. This requires a high inductive ability of the inductance of the release to form the corresponding force of the moving core, which complicates the design of the fixed core of the coil, and, therefore, complicates the entire safety device as a whole.

In the known safety devices, for connection, terminals with screw terminals are used, which reduces the convenience of operation and reduces the safety of the safety device.

In addition, the housing design of the identified known safety devices is not standardized, which, for example, does not allow them to be used as a fuse-insert (GOST 2213-79), whose housing (cartridge) is a closed insulating housing with conductive contact tips. This deprives the identified known safety devices that use an electromagnetic release, versatility and limits the scope of their use.

There is the problem of creating an improved overcurrent safety device that eliminates the possibility of tripping due to an accidental short-term peak current overload or over current overload caused by a surge voltage.

The existing problem is solved by the claimed safety device.

The essence of the claimed invention lies in the fact that in a safety device that includes a case with an electromagnetic release and a free release mechanism placed in it, the electromagnetic release switch includes a magnetic circuit with a magnetizing winding, an anchor that is spring-loaded relative to the magnetic circuit.

New is that the device is made of insulating material in the form of a pipe, the ends of which are closed rigidly fixed to them, made of conductive material, contact caps with a cylindrical contact lug coaxially with the axial line of the body, axial through holes are made in the caps, inside the case, an electromagnetic release and a free release mechanism are placed at opposite ends, while the magnetic circuit is made in the form of a ring, with the force inserted into the body of the mouth and tightly, around the perimeter covers a coil of inductance with a fixed core, in which a through axial hole is made, coaxial with the axis of the housing, in addition, a release control unit is inserted in the device, consisting of a parallel-connected self-resetting fuse and a varistor, to which the first and second terminals inductance coil is connected in parallel, while the first output is electrically connected to the magnetic core, and the second is electrically connected to the contact cap attached to the same The housing face, while the spring-loaded armature is placed on the end of the coil, facing the inside of the body, with the possibility of reciprocating movement in the direction perpendicular to the axial line of the coil core, an through hole is made in the anchor, the axis of which is parallel to the body axis, while the anchor is under the action of the unclamped spring occupies the initial position, in which the axial line of the hole made in it is at a distance from the axial line of the housing passing through the hole and shifted away from the armature spring, cr Moreover, a trigger indicator is inserted into the device, which is located at the opposite end of the case, the first end of which is placed coaxially in the contact protrusion of the corresponding contact cap with the possibility of going outside, and the second end of the pointer is placed coaxially inside the device body, while the pointer has the possibility of axial return translational movement by a fixed amount, in addition, the mechanism of free tripping includes a guide element having a circle in cross section, which Avlen into the device body coaxially, with force, with the possibility of reciprocating movement, while from the guide element on the side facing the release, there is a sleeve fixed in it fixedly and coaxially, made of conductive material, the protruding end of which is designed to be hooked in the through hole of the armature, which is made with the possibility of fixing the hook, at the same time, on the opposite side of the guide element is placed a conductive breaking spring, inside which is coaxially one is placed damping spring, and the first end of the breaking spring is electrically connected to the corresponding contact cap, and the first end of the damping spring is fixed on the second end of the trigger indicator, while the second end of the breaking spring is fixed on the sleeve, besides, through the holes in the sleeve, at anchor, in the core of the coil and through the hole in the second contact cap, a monofilament is stretched, one end of which is fixed outside on the second contact cap, and the other end is rigidly connected to orym amortization end spring, the thread is fixed in a tensioned state when the compressed springs. In addition: the outer end of the sleeve is made in the form of a fungus; monofilament is a fishing line; inside the through hole in the armature on the spring side, parallel to the walls of the hole, is made with a stepped recess, with the base of the step facing the inside of the case; the second end of the trigger pointer is spring-loaded on the side of the conductive contact washer, which is for the second end of the pointer guide and is pressed to the end of the case with a corresponding contact cap at a distance from its inner surface, providing the possibility of axial reciprocating movement of the pointer to a fixed value; the guide element in the mechanism of free tripping is made in the form of a cup, which is inserted into the device case with the possibility of reciprocating movement and facing the bottom towards the release, while the sleeve is fixed in the bottom of the cup, and inside the cup there is a conductive breaking spring inside which is coaxially freely placed depreciation spring, while the second end of the breaking spring is fixed on the inner side of the glass on the hub, and the second end of the damping spring is rigidly connected to the second the end of the monofilament, stretched through the sleeve; the trigger indicator is made of conductive material, and the first end of the release spring is fixed at the second end of the trigger indicator; the control unit of the release is connected to the leads of the inductor via a two-sided circuit board made in the form of a washer fixed in the device case with the possibility of providing electrical contact of the corresponding leads of the inductor with the magnetic core and the contact cap; the double-sided board with the conductor layer bordering the perimeter is pressed to the magnetic core of the inductor by a contact cap attached to the release side, and the upper conductor bordering along the perimeter is pressed to the inner surface of the cap, while the leads of the inductance are soldered to the lower and upper conductive surface of the mounting plate.

In the implementation of the claimed safety device is achieved technical result:

simplification of the design of the safety device, by simplifying the design of the release and the mechanism of free tripping;
the possibility of a selective response to changes in the current in the protected circuit, namely: the lack of response to changes in current caused by pulsed overvoltages, including random peak voltages;
exclusion of unreasonable shutdown of the consumer;
the possibility of obtaining reliable information about the operation of the device;
improving the usability and safety of the safety device;
expansion of the field of use by creating a universal safety device due to the possibility of standardization of the safety device.

The stated technical result is achieved as follows.

The essential features of the claims: "A safety device including a housing with an electromagnetic release and a free release mechanism placed in it, while the electromagnetic release includes a magnetic circuit with a magnetizing winding, an anchor that is spring-loaded relative to the magnetic circuit, ..." are an integral part of the claimed method and provide implementation, and, therefore, ensure the achievement of the stated technical result.

In the inventive safety device, the device case is made of insulating material in the form of a pipe, the ends of which are closed rigidly fixed to them, made of conductive material, contact caps with a cylindrical contact lug coaxially with the axial line of the case, which simplifies installation and replacement of the safety device during use.

In accordance with GOST 2213-79 "AC fuses for voltage of 3 kV and above", the fuse case (cartridge) is a closed insulating case with conductive contact tips. As a result, in the proposed design, the case of the declared safety device can be standardized both in appearance and in overall dimensions, in accordance with GOST 2213-79, which gives the declared safety device versatility and allows to use as a fuse-insert, expanding the area use, as well as simplifying and increasing the ease of operation and safety of the safety device (ease of installation when replacing, excluding connecting installation works, since on each side the contact caps are transformed into a cylindrical contact protrusion coaxially with the axial line of the housing, which facilitates the installation of the declared safety device).

Execution of the protective device case in the form of a pipe allows placing the electromagnetic release device and the free tripping mechanism inside the case at opposite ends, which ensures the operability of the claimed device. In addition, since the claimed form of the housing allows the magnetic core to be made in the form of a ring, this allows us to simplify the design of the electromagnetic release, namely: to perform an inductance coil in the form of a solenoid, simplifying the shape of the fixed core as much as possible. At the same time, it is possible to compactly place the magnetic core and the coil in the device case, taking into account its geometric shapes, with the most complete filling of the internal space, ensuring the compactness of the declared safety device as a whole. Due to the fact that the magnetic core is made in the form of a ring, is inserted into the device body tightly, and around the perimeter it covers the inductance with a fixed core, the operability of the electromagnetic system with the optimum value of electromagnetic induction is ensured.

The device includes a trip unit control unit consisting of a self-resetting fuse and a varistor connected in parallel, to which the inductance coil is connected in parallel, one of which is electrically connected to the magnetic circuit, and the second is electrically connected to the contact cap attached to the same end of the housing. As a result, the control node together with the inductor is connected in series to the protected circuit. Moreover, since the connection of the fuse and the varistor with the coil is parallel, the current through the release coil depends on the size of their resistance.

Self-resetting fuses are devices that limit the current in the circuit, but unlike conventional fuses, they do not lose their functionality after they are triggered. As a rule, self-resetting fuses are PPTC thermistors. The short name PPTC (Polymeric positive temperature coefficient coefficient device) is a polymer device with a positive temperature coefficient of resistance. For the first time such devices were discovered, described and patented by Bell Labs in 1939 (patent number US # 2,258,958).

The principle of operation of the self-resetting fuse (hereinafter referred to as thermistor) is based on the ability of the polymer to change the conductive structure when heated. At room temperature, the polymer has a crystalline structure, so that the movement of charged particles occurs in an orderly manner, and the current in the circuit is determined by the operating value of the load resistance. In the event of an emergency, the current in the circuit increases sharply, heating the polymer. At a certain temperature, corresponding to a given nominal response current, the thermistor triggers, namely the phase state of the polymer changes from crystalline to amorphous. As a result, the resistance of the thermistor increases dramatically and the current in the circuit is determined by the value of its resistance. In this case, the thermistor changes from a conducting state to a discontinuous state. the thermistor remains in a “hot” state, providing constant protection until current passes through it, causing a transition to this state, or until the causes of its operation are eliminated. After eliminating the causes of operation, the thermistor cools and its resistance returns to the nominal value. ()

The resistance of the varistor is determined by the operating voltage. In the inventive device, a varistor is used to suppress surge overvoltages, including the occurrence of random peak overvoltages, which is widely known ().

In this case, due to the parallel connection of the thermistor and the varistor with the inductor, the current through the release coil depends on the magnitude of their resistance. In the rated operation mode at the rated current that does not trigger the thermistor (transition to the breaking state), all the current passes through the thermistor, since the resistance of the inductance coil and the varistor is much higher than the resistance of the thermistor. Trip does not work.

In the mode of pulse overvoltages, the thermistor during the lifetime of the pulse does not have time to change its resistance to a discontinuous state and remains in the conducting state. In the pulse overvoltage mode, the resistance of the varistor decreases and a current flows through it corresponding to its resistance (damping of the overvoltage pulses with the varistor). As a result, in a surge overvoltage mode, the electric mode of the inductor does not change and the release does not work.

In the event of an emergency, the current in the circuit increases sharply, heating the polymer thermistor. At a certain temperature, corresponding to a given rated current of operation, the thermistor triggers and the thermistor changes from a conducting state to a discontinuous state. Maximum varistor resistance (varistor closed). In this case, all the current passes through the electromagnetic release, which opens the emergency circuit.

From the foregoing, it follows that, due to the introduction of the release control unit into the inventive safety device, the release responds selectively to changes in the current in the protected circuit, namely does not respond to changes in current caused by pulsed overvoltages. As a result, the possibility of unreasonable shutdown of the consumer is excluded. Thus, as a result of using an electromagnetic release together with a control unit containing a varistor and a thermistor connected in parallel, a synergistic effect occurs, which results in the possibility of using the performance of the electromagnetic release while simultaneously ensuring selectivity, namely: the release of the release only under the action of current with the network frequency , excluding operation in case of pulsed overvoltages or from random pulsed overloads.

The control unit of the release is connected to the leads of the inductor by means of a board made in the form of a washer, which takes into account the geometric shape of the housing and the magnetic core and makes it possible to fix it in the housing. The two-sided mounting plate allows it to be fixed in the device case with the possibility of providing electrical contact of the corresponding inductance coils with the magnetic core and the contact cap. At the same time, the electrical contact of the respective leads of the inductor with the magnetic core and the contact cap is ensured by the fact that the double-sided board is provided with a lower and upper conductor layer bordering the perimeter, and with a conductive contact pin attached to the magnetic core of the inductor layer is pressed to the inner surface of the cap, while the leads of the inductance are soldered to the lower and upper conductive Nost of the circuit board, respectively.

Thus, it follows from the foregoing that the release control unit performs the function of an overload criterion, which makes it possible to organize the release of the release only under the action of a current with a mains frequency exceeding the specified value. In this case, the claimed safety device with an electromagnetic release device, in contrast to the known ones, works selectively, excluding operation in the event of pulsed overvoltages or from random pulsed overloads.

In the claimed safety device, the ends of the case are closed tightly fixed on them, made of conductive material, contact caps with a cylindrical contact protrusion coaxially with the axial line of the case. At the same time, axial through holes are made in caps coaxially with the axis of the housing. The proposed design of the contact cap allowed to introduce into the inventive safety device an operation indicator, which is located inside the case at the end opposite to the electromagnetic releaser. In this case, the first end of the pointer is placed coaxially in the contact protrusion of the corresponding contact cap with the possibility of going out, and the second end of the pointer is placed coaxially inside the fuse body. Since the first ends of the shut-off and damping spring are fixed on the second end of the trigger indicator, it is possible to axially reciprocate the pointer depending on the state of the springs (compressed, decompressed), i.e. depending on the state of the safety device (rupture, conductive, respectively). As a result, the position of the pointer corresponds to the state of the safety device.

The second end of the trigger pointer is spring-loaded on the side of the conductive contact washer, which is a guide for the second end of the pointer and is pressed to the end of the case with a corresponding contact cap at a distance from its inner surface, allowing the axial reciprocating movement of the pointer to a fixed value at a distance that provides the working stroke of the pointer when the safety device is installed in a working state, in which its first end is inside the contact cap. Thus, due to the contact washer, a space is created for compressing the pointer spring, which limits the stroke of the pointer, preventing the second end from moving and fixes the position of the first end of the pointer inside the contact cap and outside of it both at the conductive and the rupture state of the declared safety device. As a result, in the claimed device, the position of the pointer is informatively reliable, corresponding to the state of the safety device. In addition, the proposed design of the pointer is autonomous, not allowing the re-activation of the monitored circuit by means of the trigger indicator (in the prototype - the trigger indicator button for supplying voltage), which increases the safety of using the declared safety device. In this case, the pointer does not exert electrical influence on the protected circuit, in particular, does not cause unwanted leakage currents, since it has a mechanical principle of operation, which also increases the safety of the device as a whole, since it eliminates unreasonable shutdown of the consumer.

In addition, the presence of a trigger indicator in the safety device, as well as the possibility of using it to turn on automation as a shock trigger indicator, meet the requirements of the standard “AC fuses for a voltage of 3 kV and above” GOST 2213-79, which, in conjunction with the stated version the case of the safety device, provides the possibility of standardization of the device and gives the declared safety device the property of universality.

The anchor, spring-loaded relative to the magnetic circuit, is placed on the end of the coil, facing the inside of the case, with the possibility of reciprocating movement in the direction perpendicular to the axial line of the core of the coil. The anchor has a through hole, the axis of which is parallel to the axis of the body. Under the action of a spring-loaded spring, the anchor occupies an initial position, in which the axial line of the hole made in it is at a distance from the axial line of the housing passing through the hole and shifted away from the spring of the armature. In this case, the through hole of the armature is made with the possibility of fixing a hook made at the end of the sleeve connected to the breaking spring. In this case, the fixing of the hook is carried out due to the fact that the hook is made in the form of a fungus; inside the through hole in the anchor from the spring side, parallel to the walls, there is a stepped recess, with the base of the step facing inward. As a result, the hook, when it enters the hole in the anchor, depresses the spring of the anchor, is installed on the step, after which the anchor under the action of the spring returns to its original state. The elasticity of the armature spring allows the armature to move freely in the direction of the magnetic conductor under the action of the hook that enters its hole (if there is no anchoring effect of the electromagnetic induction of the coil).

In this case, thanks to the proposed implementation of the armature and the hook of the breaking spring, the interaction of the armature and the hook does not convert one type of movement into another, since the movement of the hook under the influence of the movement of the armature is a continuation of the movement of the anchor. This reduces the requirements for the quantitative value of electromagnetic induction, which leads to the movement of the moving core, and, as a result, simplifies the design of the fixed core of the inductor and the entire electromagnetic system of the release as a whole, and, consequently, simplify the claimed safety device.

The free trip mechanism contains a guide element having a circumference in cross section, which is inserted into the device body coaxially, with force, with the possibility of reciprocating movement, which makes it possible for it to perform its main function - to maintain the direction of movement.

From the center of the guide element on the side facing the release, there is a sleeve made of conductive material fixed in it fixedly and coaxially. At the same time, on the opposite side of the guide element is placed a conductive breaking spring, inside of which a damping spring is placed coaxially freely. Since the first end of the tripping spring is electrically connected to the corresponding contact cap, and the second end of the tripping conductive spring is fixed to a sleeve also made of a conductive material, the sleeve is electrically connected to the corresponding contact cap through the breaking current spring.

In addition, since the sleeve is fixedly mounted in the guide element, which is inserted into the device body with the possibility of reciprocating movement, a kinematic connection of the release spring and the guide element is simultaneously provided.

Through the holes in the sleeve, in the anchor, in the core of the coil and through the hole in the second pin cap, a monofilament is stretched, which can be used as a fishing line. One end of the monofilament is fixed outside on the second pin cap, and the second end is rigidly connected inside the cup to the second end of the shock-absorbing spring, the first end of which is fixed on the second end of the trigger pointer. Since the sleeve is fixed in the guide element stationary, the result is a kinematic connection of the pointer, damping spring, guide element and monofilament, which allows them to move simultaneously under the influence of muscular effort exerted on the monofilament.

Moreover, since the guide element of the tripping mechanism is inserted into the device body coaxially with the possibility of reciprocating movement, the springs are kinematically connected with it, and the protruding end of the sleeve is made in the form of a fungus, with appropriate tension of the springs under the action of the monofilament hook anchor spring, and is installed in the hole on the step made in it. As a result, after fixing the hook, the armature spring and the armature itself are set to their original state, in which the axial line of the hole made in it is at a distance from the axial line of the housing passing through the hole and shifted away from the armature spring, which prevents the hook from spontaneously sliding out .

Since the sleeve is electrically connected to the corresponding contact cap through the disconnecting conductive spring, after hooking it is ensured that the electromagnetic release is connected to the circuit. The result is an electrical connection of the contact caps inside the safety device.

Since the second end of the damping spring is connected to the monofilament, after the hooking is completed, when the muscular effect on the monofilament stops, the damping spring returns to its original state, dragging the second end of the monofilament, which also returns to its original tensioned state with compressed springs, fixing the position of the damping spring in the case. As a result, when the hook is opened, the damping spring takes on the shock effect of the bottom of the glass.

In this case, the guide element can be made, for example, in the form of a glass, which simultaneously performs the function of the casing of the mechanism and the guide element. The glass is inserted into the device body coaxially with the possibility of reciprocating movement and facing the bottom of the release. From the bottom of the glass acts sleeve, fixed in the glass coaxially and motionless. A conductive breaking spring is placed inside the cup, inside which a damping spring is coaxially placed. The second end of the breaking spring is fixed on the inner side of the glass on the sleeve, and the other end of the shock-absorbing spring is connected to monofilament. As a result, after the hooking, when the muscular effect on the monofilament stops, the depreciation spring returns to its original state, due to the impact of the tensioned thread on it. When the hook is opened, this spring takes on the shock effect of the bottom of the glass.

The implementation of the guide element in the form of a glass and the placement of springs inside the glass ensures the stability of the position of the springs relative to each other, both in a static state and when stretching, which ensures the operability of the device. These attachment of the second ends of the springs provide a kinematic connection with the glass, which also ensures the operability of the device, and, therefore, ensures the achievement of the stated technical result.

From the above follows. The body of the safety device in the form of a pipe, the ends of which are closed rigidly fixed to them, made of conductive material, contact caps with a cylindrical contact lug coaxially with the centerline of the body, as well as the introduction of an operation indicator comply with the requirements of the standard AC fuses for voltage of 3 kV and above GOST 2213-79, i.e. in the proposed design of the case and the indicator of operation, the declared safety device can be standardized both in appearance and dimensions, in accordance with GOST 2213-79, which gives the declared safety device versatility and allows to use as a fuse - insert, expanding the area of use, as well as simplifies and improves the usability and safety of the safety device (ease of installation when en, exception of connecting installation works, since on each side of the contact caps go into a cylindrical contact ledge coaxially with the axial line of the housing, which contributes to and facilitates the installation of the declared safety device).

In addition, the introduction of the operation indicator provides the possibility of receiving a visual signal about the presence of an emergency situation and the operation of the safety device, which is informatively reliable.

Introduction to the inventive safety device of the control unit of the release eliminates the possibility of unreasonable shutdown of the consumer, since the control unit of the release performs the function of overload criterion and allows organizing the release of the release only under the action of a current with a network frequency exceeding the specified value. In this case, the claimed safety device with an electromagnetic release device, in contrast to the known ones, works selectively, excluding operation in the event of pulsed overvoltages or from random pulsed overloads.

In addition, in the inventive safety device during the interaction of the armature and the hook, both when the electric circuit is closed and during an emergency break, there is no conversion of one type of movement into another, since the movement of the hook under the influence of the movement of the armature is a continuation of the movement of the anchor. This allows you to reduce the required force on the armature, depending on the magnitude of the generated electromagnetic induction, and, as a consequence, simplify the design of the fixed core of the inductor and the entire electromagnetic system of the release as a whole.

The simplicity of the execution of the free tripping mechanism, the trigger indicator, the possibility of reducing the operating value of electromagnetic induction, which simplifies the electromagnetic system device, the simplicity of recovering from operation (using monofilament) together simplify the declared safety device compared to the prototype.

Thus, it follows from the foregoing that the claimed safety device solves the problem of creating an improved current safety device that eliminates the possibility of triggering by an accidental short-term peak current overload or by current overload caused by a pulse overvoltage. In the implementation of the claimed safety device is achieved technical result:

The invention is illustrated by drawings, which shows the preferred execution of the device, in particular:

Figure 1

contains safety device in the initial state, vertical section.

Figure 2

contains safety device in working condition, vertical section.

Figure 3

contains a release control unit mounted on a two-sided mounting plate.

4

contains a release control unit mounted on a two-sided circuit board, type A.

The claimed safety device comprises a housing 1 in the form of a pipe with contact caps 2, 3 with a cylindrical contact lug, an electromagnetic release 4, a release control unit 5, a free release mechanism 6, an operation indicator 7.

Electromagnetic release 4 contains a magnetic core 8, an inductor 9 with a magnetic core 10 and an anchor 11.

The release control assembly 5 contains a self-resetting fuse 12 (thermistor) connected in parallel and a varistor 13. Assembly 5 is assembled on a two-sided circuit board 14.

The free release mechanism 6 comprises a guide element 15, a sleeve 16, a shut-off spring 17, a damping spring 18, and a monofilament 19.

The housing 1 of the device is made of insulating material in the form of a pipe, the ends of which are closed rigidly fixed to them, made of conductive material, contact caps 2, 3 with a cylindrical contact lug coaxially with the axial line of the housing. In the caps 2, 3, axial through holes are made coaxially with the axis of the housing 1. Inside the housing 1, electromagnetic release 4 (hereinafter - release) and free release mechanism 6 (hereinafter - release mechanism) are placed at opposite ends.

The magnetic circuit 8 is made in the form of a ring, with force inserted into the device case 1 and tightly, around the perimeter it covers the inductor 9 with a fixed core 10, in which a through axial hole is made, coaxial with the axis of the case 1.

To the terminals of the parallel-connected thermistor 12 and the varistor 14, the inductance 9 is connected in parallel by the first and second leads, the first lead is electrically connected to the magnetic circuit 8, and the second is electrically connected to the contact cap 3 fixed on the same end of the housing 1.

The double-sided mounting board 14 is made in the form of a washer (FIG. 2) fixed in the device case 1 with the possibility of providing electrical contact of the corresponding leads of the inductance 9 with the magnetic core 8 and the contact cap 3. To ensure the corresponding electrical contacts the double-sided board 14 is bordered along the perimeter the conductive layer is pressed to the magnetic conductor 8 of the inductance coil by the 4 contact cap 3 fixed on the side of the release. The upper bordering around the perimeter of the conductive layer of the board 14 is pressed to the inner surface of the cap 3. The first and second terminals of the inductance are soldered to the lower and upper conductive surface of the circuit board, respectively.

Spring-loaded anchor 11 is placed on the end of coil 9, facing the inside of the housing 1, with the possibility of reciprocating movement in the direction perpendicular to the axial line of the core 10 of the coil 9. The anchor 11 has a through hole 20, the axis of which is parallel to the axis of the body 1. the spring 21 takes the initial position, in which the axial line of the hole 20 made in it is at a distance from the axial line of the housing 1 passing through the hole and shifted away from the spring 21 of the armature 11. Inside the through The holes in the anchor 11 from the spring 21 side parallel to the walls of the hole are made with a stepped recess, while the base of the step is facing the inside of the case.

The pickup indicator 7 is located at the end of housing 1, opposite to the releaser 4. The first end 22 of the pointer 7 is placed coaxially in the contact lug of the corresponding contact cap 2 with the possibility of going out. The second end 23 of the pointer is placed coaxially inside the housing 1 of the device. Pointer 7 has the possibility of axial reciprocating movement of a fixed value. The second end 23 of the trigger pointer 7 is spring-loaded by the spring 25 on the side of the conductive contact washer 26, which is a guide for the second end 23 of the pointer 7 and is pressed to the end of the body 1 by the corresponding contact cap 2 at a distance from its inner surface, allowing axial reciprocating movement 7 by a fixed amount.

The guide element 15 has a circumference in cross section and is inserted into the device body coaxially, with force, with the possibility of reciprocating movement. From the guide element 15 on the side facing the release 4, there is a sleeve 16 fixed in it fixedly and coaxially, made of conductive material, the protruding end of which is adapted to be hooked in the through-hole of the armature 11, which is made to fix the hook made, for example, in the form of a fungus 24.

On the opposite side of the guide element 15 is placed a conductive breaking spring 17, inside of which a damping spring 18 is placed coaxially freely.

The first end of the release spring 17 is electrically connected to the corresponding contact cap 2, for example, the operation indicator 7 is made of conductive material, and the first end of the release spring is fixed at the second end 23 of the operation indicator 7. The second end of the release spring 17 is fixed on the sleeve 16.

Through the holes in the sleeve 16, in the anchor 11, in the core 10 of the coil 9 and through the hole in the second contact cap 3, the monofilament 19 is stretched, one end of which is fixed externally on the second contact cap 3, for example, terminated in a knot and fixed in the sleeve. The second end of the monofilament is rigidly connected to the second end of the damping spring 18, also, for example, terminated by a knot and fixed in the sleeve. The first end of the depreciation spring is fixed at the second end 23 of the pointer 7. In this case, the monofilament 19 is fixed in the tensioned state. As monofilament can be used fishing line.

The guide element 15 in the mechanism of free tripping 6 can be made in the form of a cup, which is inserted into the device case 1 with the possibility of reciprocating movement and facing the bottom of the release 4. The sleeve 16 is fixed in the bottom of the cup, and inside the cup a conductive breaking spring 17 , inside of which a damping spring 18 is coaxially placed freely. The second end of the breaking spring 17 is fixed on the inner side of the sleeve on the sleeve 16, and the second end of the damping spring is rigidly connected to torym end monofilament 19 stretched through the sleeve 16.

The claimed safety device is assembled as follows. A spring 25 is pushed onto the second end 23 of the trigger pointer 7, which is pressed against the conductive contact washer 26. A damping spring 18 is placed inside the release spring 17. The first ends of the

spring

17, 18, 18. on the sleeve 16. Through the sleeve 16, pull the second end of the monofilament 19, terminate the junction of the monofilament 19 with the second end of the damping spring 18 and fix it in the connecting sleeve 27. The assembled unit Put the guide element 15 into the cup. In this case, the thread comes out of the sleeve. At the first end 22 of the indicator of operation 7 put on the contact cap 2 and press, turning the cap along the thread, the washer 26 to the body 1 of the device.

Then, the release 4 is assembled. Through the holes in the anchor 11 and in the core 10, the coils 9 pull the monofilament 19. The coil 9 with the core 10 and the spring-loaded anchor 11 are inserted into the magnetic core 8. Pull the monofilament 19 through the circuit board 14 and fix it on the core 10 of the coil 9 by stops (not shown). Connect the findings of the coil 4 with the node 5 control release. The assembled unit is inserted into the housing 1 of the device. For reliable fixation of the release inside the housing 1, the release rests on the guide washer 28 fixed in the wall of the housing 1, through which the monofilament 19 is also stretched. Through the hole in the contact cap 3 pull the monofilament and close the opening 3 to the magnet circuit and to the inner surface of the cap 3. At the end of the assembly, the monofilament is brought into a stretched state, for which purpose it is tensioned until the feeling of light resistance of the

springs

17, 18. The free end of the thread is fixed with any an aid, for example, is passed through a fixing sleeve and terminated in a knot.

The device works as follows. In the initial state, the hook mechanism of the free tripping is at a distance from the anchor corresponding to the length of the monofilament. The first end of the actuation indicator protrudes out of the contact cap 2. To bring the safety device into working condition, pull the monofilament out of the device body by the end fixed outside the cap 3. As a result, the guide element together with the

springs

17, 18 begins to move toward the release. Monofilament is pulled out to get a sound signal - a click, which is formed as a result of hitch 24 of the sleeve 16 in the hole 20 of the armature due to the step made in it. As a result, a conductive spring connected to it, electrically connected to the cap 2, closes the electrical circuit between the contact caps 2 and 3. In this case, the second end of the operation indicator is shifted deep into the housing, carried along by the release spring. As a result, the first end of the pointer is fixed inside the contact protrusion of the cap 2. The monofilament is released and it returns to its original tensioned state. At the same time, the damping spring returns to its original state. A current begins to flow through the device. In normal mode at a rated current that does not trigger the thermistor (transition to the breaking state), all the current passes through the thermistor, since the resistance of the inductance coil and the varistor is much higher than the resistance of the thermistor. Trip does not work.

In the mode of pulse overvoltages, the thermistor during the lifetime of the pulse does not have time to change its resistance to a discontinuous state and remains in the conducting state. At the same time, in the mode of pulse overvoltage, the resistance of the varistor is significantly reduced (damping of the overvoltage pulses by the varistor). As a result, in a surge overvoltage mode, the electric mode of the inductor does not change and the release does not work.

In the event of an emergency, the current in the controlled circuit increases dramatically, heating the polymer of the thermistor. At a certain temperature, corresponding to a given rated current of operation, the thermistor triggers and the thermistor changes from a conducting state to a discontinuous state. The resistance of the varistor is much higher than the resistance of the inductor. In this case, all the current passes through the electromagnetic release. Under the action of the increased electromagnetic flux, the anchor compresses its spring and shifts away from the axial body, while simultaneously shifting the hole made in it. The hook slides off the step and opens electrical contact with the release. A “shooting” of the hook occurs and the hook together with the guide element rapidly falls on the shock-absorbing spring, which transmits the impact force to the second end of the trigger indicator and it comes out of the cap 2, indicating that the safety device has been activated

Claims

A safety device including a case with an electromagnetic release device and a free release mechanism placed in it, while the electromagnetic release device includes a magnetic circuit with a magnetizing winding, an anchor that is spring-loaded relative to the magnetic circuit, characterized in that the device case is made of insulating material in the form of a pipe, the ends of which are closed rigidly mounted on them, made of conductive material, contact caps with a cylindrical contact projection coaxially The hull lines of the case, axial through holes are made in caps coaxially with the axis of the case, an electromagnetic release and a free release mechanism are placed inside the case at opposite ends, while the magnetic circuit is made in the form of a ring, is inserted into the device body tightly, and around the perimeter covers an inductance coil with a fixed core, in which a through axial hole is made, coaxial with the axis of the housing; moreover, a release control unit is inserted into the device, consisting of a parallel connection A self-resetting fuse and a varistor, to which the inductance coil is connected in parallel by the first and second leads, the first lead is electrically connected to the magnetic circuit, and the second is electrically connected to the contact cap attached to the same end of the case, while the spring-loaded anchor is placed on the end of the coil, facing the inside of the body, with the possibility of reciprocating movement in the direction perpendicular to the axial line of the core of the coil, a through hole is made in the anchor, the axis of which is parallel to the axis of the body, while the anchor under the action of the decompressed spring takes the initial position in which the axial line of the hole made in it is at a distance from the axial line of the body passing through the hole and shifted away from the armature spring, moreover, a pointer is entered into the device actuation, which is placed in the opposite end of the case, the first end of which is placed coaxially in the contact protrusion of the corresponding contact cap with the possibility of going outside, and the second end of the pointer I am placed coaxially inside the device case, while the pointer has the possibility of axial reciprocating movement by a fixed amount, in addition, the free tripping mechanism contains a guide element having a circumference in cross section that is inserted into the device case coaxially, with effort, with the possibility of returning -accessible movement, with the sleeve, fixed in it fixedly and coaxially, made of conductive, coming out of the guide element from the side facing the releaser material, the protruding end of which is made with the possibility of a hook in the through hole of the armature, which is adapted to fix the hook, while on the opposite side of the guide element a conductive breaking spring is placed, inside which the damping spring is coaxially freely placed, the first end of the breaking spring is electrically connected with the corresponding contact cap, and the first end of the shock-absorbing spring is fixed on the second end of the trigger pointer, with the second horse the breaking spring is fixed on the sleeve, besides, through the holes in the sleeve, in the anchor, in the core of the coil and through the hole in the second contact cap, the monofilament is stretched, one end of which is fixed outside on the second contact cap, and the second end is rigidly connected to the second end of the shock absorber springs, while the thread is fixed in the tensioned state with compressed breaking and cushioning springs.
The safety device according to claim 1, characterized in that the outer end of the sleeve is made in the form of a fungus.
The safety device according to claim 1, wherein the monofilament is a fishing line.
The safety device according to claim 1, characterized in that inside the through hole in the armature on the spring side, parallel to the walls of the hole, is made with a stepped recess, with the base of the step facing the inside of the case.
A safety device according to claim 1, characterized in that the second end of the actuation indicator is spring-loaded from the side of the conductive contact washer, which is for the second end of the guide pointer and is pressed to the end of the case with a corresponding contact cap at a distance from its inner surface, enabling axial reciprocating move the pointer to a fixed value.
The safety device according to claim 1, characterized in that the guide element in the mechanism of free tripping is made in the form of a cup, which is inserted into the device body with the possibility of reciprocating movement and facing downward in the direction of the release, while the sleeve is fixed in the bottom of the cup, and inside a conductive breaking spring is placed inside which a damping spring is placed coaxially freely, while the second end of the breaking spring is fixed on the inner side of the sleeve to the sleeve, and second amortization spring end is rigidly connected to the second end of the monofilament, stretched across the sleeve.
The safety device according to claim 1, characterized in that the operation indicator is made of a conductive material, and the first end of the release spring is fixed at the second end of the operation indicator.
Safety device according to claim 1, characterized in that the release control unit is connected to the inductance terminals by means of a two-sided circuit board made in the form of a washer fixed in the device case with the possibility of providing electrical contact of the corresponding inductance terminals with the magnetic core and contact cap.
A safety device according to claim 7, characterized in that the double-sided board with the bottom bordering around the perimeter of the conductive layer is pressed to the magnetic core of the inductor by a contact cap fixed on the side of the release, and the top bordering along the perimeter of the conducting layer is pressed to the inner surface of the cap, while the leads of the inductor soldered to the lower and upper conductive surface of the circuit board, respectively.