ES3014464T3 - Safety device and three-pole base - Google Patents

Abstract

Safety device and three-pole base. The device (1) comprising a switch element (104) in series with a fuse (103), the switch (103) having an open state and a closed state; a manual actuator (105) for opening and closing said switch element (104); measuring means (106) for measuring at least one operating parameter of the device (1); and a control module (107) for disarming the device when the operating parameter meets a predetermined condition; wherein said disarming comprises acting on the switch element (104) to cause said switch element (104) to pass from the closed state to the open state.

Description

DESCRIPTION

Safety device and three-pole base

Field of the invention

The invention relates to the field of electrical installations, particularly electrical distribution boards comprising three-pole fuse bases.

More specifically, the invention relates to an electrical safety device configured to be installed in a three-pole fuse holder base, comprising two terminals between which an electrical branch is defined, said branch being provided with a fuse configured to interrupt the flow of electrical current in said branch in the event of a fusion.

The invention also relates to a corresponding three-pole fuse holder base.

State of the art

In the field of electrical installations, it is common to use fuses designed to blow when the current intensity exceeds a threshold, thus interrupting the flow of current. This blowing is generally not instantaneous, but requires that the threshold be exceeded within a time window. Thus, by selecting fuses with the appropriate characteristics, it is possible to create safety features that prevent the flow of excessively high currents that could cause damage or accidents downstream. In particular, in the field of low-voltage installations, three-pole fuse bases are used, into which three of these fuses are inserted.

This type of device offers high safety, as it provides a physical interruption in overcurrent situations. However, it has the disadvantage that, once blown, the fuse must be replaced with a new one, which increases maintenance costs. Furthermore, in cases where line operations require cutting off the power supply, an operator must physically remove the fuse to cut off the current.

For these reasons, alternative solutions to fuses have also emerged, such as circuit breakers. These devices are calibrated to cut off the current under specific conditions, usually using bimetallic elements. They have the advantage of allowing resetting after a power outage, generally using a manual actuator or a motorized remote control, which significantly reduces maintenance costs compared to fuses.

However, both fuse-based and circuit-breaker-based devices have the disadvantage of being difficult to adapt to different power outage situations. Furthermore, conventional circuit breakers are not particularly suited to the voltage and current conditions found in low-voltage distribution centers. In particular, the level of safety offered by these circuit breakers may be lower than that offered by fuses.

Therefore, an electrical safety device that provides a high level of safety while simultaneously reducing maintenance costs and providing flexibility in selecting line-cutting criteria is desirable.

Document WO 2016/042290 A1 discloses a power management device including a circuit breaker connected to a coupling assembly that connects terminals of a fuse assembly to the circuit breaker. The coupling assembly includes a fuse, or a connecting bar, which may be removably supported within the coupling assembly and provides an electrical path for current flow through the coupling assembly and the circuit breaker. The circuit breaker is connected to a remote SCADA system that allows remote operation of the device. Since the switching device can be operated remotely, the power management device of the present invention therefore provides a remotely operated device that can be installed in the space of a conventional fuse. This reduces supply management time since it can be reset remotely. The provision of a series fuse increases the electrical breaking capacity. The power management device may be permanently installed or may be installed for a short period to assist in maintaining supply until the fault is located. Downtime is minimized in a conventionally managed network, and migration to a smart grid is facilitated, while operator safety is increased through independent and/or remote manual switching. Furthermore, it can be installed selectively in existing or new equipment. The document discloses all the features of the preamble of claim 1.

Description of the invention

The invention aims to provide an electrical safety device of the type indicated at the beginning, which allows the problems described above to be solved.

This purpose is achieved by an electrical safety device according to claim 1. This electrical safety device is of the type indicated at the beginning, and also comprises:

- a switching element, provided in said branch and connected in series with said fuse, said switching element having a closed state in which it allows the passage of electric current, and an open state in which it prevents the passage of electric current;

- a manual actuator, configured to cause said switching element to pass from said closed state to said open state and vice versa;

- measuring means, configured to measure at least one operating parameter of said safety device; and

- a control module, configured to carry out a disarming in the event that said at least one operating parameter meets a predetermined condition, wherein said disarming comprises acting on said switching element to cause said switching element to pass from said closed state to said open state.

In this way, the switching element and the fuse are connected in series. Thus, the switching element acts as the first disconnection line, while the fuse provides added safety: even in the event of a switch failure, if the current is excessive, the fuse will perform its function and cut the line. In turn, the disengagement of the switching element is controlled by the control module, allowing the same device to be used for different predetermined conditions, for example, different current thresholds, temperature, etc. This predetermined condition is based on an operating parameter measured on the device itself by the measuring means. Consequently, in normal operation, the line is cut off by the switching element, based on a predetermined condition that can be adapted to each installation, thus providing flexibility to the device. Since the fuse does not blow in this normal operation, it does not need to be replaced in the event of a power outage, thus minimizing maintenance costs. Nor is it necessary for an operator to remove the fuse to cut the line, since the manual actuator allows this operation by acting on the switching element.

On the other hand, if any component fails, such as the switching element or the control module, and the power supply is not disconnected, the fuse provided in the device will blow. This ensures the device's safety level is equivalent to that of fuses used in conventional technology, but with the addition of the technical advantages described above during normal operation.

Preferably, said control module is additionally configured to carry out a reset, which comprises acting on said switch element to cause said switch element to pass from said open state to said closed state, which allows the device to be reset without the need for an operator to physically move to the place of use of the device to carry out the reset by actuating said manual actuator.

Preferably, said control module is additionally configured to initiate said reset when a predetermined reset time has elapsed since said disarming. This allows for automatic reset after a predetermined time, which provides the device with autonomy, allowing it to automatically reset itself and allow current to flow through the line without the need for operator intervention. This type of functionality is particularly advantageous in situations such as current surges, for example, due to a lightning strike.

Preferably, said control module is additionally configured to perform at least one retry if a disarming occurs immediately after said reset, thereby increasing the device's autonomy with respect to resetting. Preferably, the total number of retries is limited to a predetermined number of retries, such that no retries are made if the conditions that triggered the line cutoff persist for an extended period, which generally implies that it is not a one-time problem.

Preferably, said operating parameters comprise a measurement of electric current in said branch, and said predetermined condition comprises at least one of the conditions where:

- said electric current measurement exceeds a threshold current; and

- said electric current measurement exceeds a threshold current for a threshold time.

The first condition is met when a threshold current value is exceeded, while the second condition requires a threshold current to be exceeded within a time window. The two threshold currents can be different. This allows the device to be disarmed in the event of occasional current spikes and/or a prolonged current surge. Preferably, for the second condition, the threshold time is a function of the threshold current, such that the higher the threshold current, the shorter the threshold time.

Preferably, said measuring means comprise a first ring current transformer, arranged around an electrical conductor of said branch. This allows a measurement of the current flowing through the branch via the induced current in said ring transformer. The measurement does not require any branch circuit from the branch itself, nor does it require the placement of other elements in series. Furthermore, the current in the measuring circuit is isolated from that flowing through the branch, which improves safety and, in particular, minimizes the risk of an overcurrent causing damage to the measuring means.

Preferably, said device also comprises a second ring-shaped current transformer, configured to electrically supply said control module, such that no external power supply is required for the device. Furthermore, similar to the case of measurement through the first ring-shaped transformer, the power supply circuit that originates from the second ring-shaped transformer to supply the device is electrically isolated from the main branch, thereby increasing the safety and robustness of the device.

Preferably, said operating parameters additionally comprise at least one of:

- a measure of temperature;

- a current measurement; and

- a measurement of voltage.

This allows said default condition to be adapted to the physical and operating conditions of the device, which means increased safety and greater flexibility in determining when it should be disarmed. It is even possible for the default condition to combine several of said measures, which would be impossible in the devices currently known in the art.

Preferably, said control module further comprises remote connection means, configured for at least one of:

- sending said operating parameters; and

- receiving commands.

This makes it possible to remotely monitor the device's operation and/or remotely send commands to the control module to perform specific actions. This increases safety and facilitates equipment maintenance, potentially minimizing maintenance costs or minimizing the time required for maintenance operations.

Preferably, said commands comprise at least one of:

- a configuration order;

- an order to begin such disarmament; and

- an order to begin such rearmament;

wherein preferably, said command to initiate said reset comprises said predetermined retry value. In this way, it is possible to remotely configure the device and/or perform a remote disarm and/or perform a remote reset after a disarm. Each of the aforementioned commands has distinct technical advantages. Thus, the configuration command allows the safety device to modify its operation. For example, modifying the current or threshold time, or said predetermined condition. The disarm command allows the device to be remotely disconnected if necessary, for example, when technical actions must be carried out in an area that require the absence of electrical power for safety reasons. Finally, the reset command allows the device to be remotely recovered, for example, after completing the aforementioned technical actions. In either case, the command is sent remotely, which facilitates the centralization of the management of several devices, for example, in different geographical areas. This centralization has the additional advantage that, with a minimized human team in terms of personnel, a plurality of locations can be managed. Furthermore, this dedicated team can receive specialized training that would be very difficult to provide to the entire team of operators who typically work on fuse-base equipment.

Preferably, said configuration order comprises at least one of:

- an order to modify said default condition, which allows modifying the conditions under which the device must be automatically disarmed;

- an order to modify said predetermined reset time, which allows the automated reset to be reprogrammed to increase or decrease the required time; and

- an order to modify the default reset retry value, allowing the device to adapt to different conditions.

Configuration commands also allow for remote, preferably centralized, modification of parameters such as those described here. This has the added advantage that, should it become necessary to comply with changing regulations over time, there is no need to physically intervene or replace the device; all that's required is to send the appropriate remote configuration commands.

Said switching element comprises a vacuum switch, of the type comprising:

- a bottle in which two electrical contacts are provided arranged in a vacuum medium;

- a first fixed terminal, connected to a first fixed rod, which communicates with the interior of said bottle and is connected to one of said electrical contacts;

- a second mobile terminal, connected to a second mobile rod, which communicates with the interior of said bottle and is connected to the other of said electrical contacts;

wherein said second terminal is movable in a direction perpendicular to said bottle between a proximal position, in which said electrical contacts are in contact and said vacuum interrupter is in said closed state, and a distal position, in which said electrical contacts are separated and said vacuum interrupter is in said open state.

Vacuum interrupters, sometimes called vacuum bottles, are elements that have been frequently used in medium- or high-voltage applications. However, their use in low-voltage applications with high current intensities, such as in the case of three-pole fuse bases, is unknown. Thus, one object of the invention is the use of vacuum interrupters as switching elements for electrical safety devices configured for installation in three-pole bases. This type of switch has the advantage that the movement distance that its elements must travel to open and close the current flow is very short compared to other types of switches, such as bimetallic circuit breakers. The reason for this is the high electrical rigidity of the vacuum inside the bottle, which minimizes the occurrence of electric arcs. This short distance means that the resulting safety device also does not require large mechanical movements, and the operating time of the vacuum interrupters is very fast compared to other known alternatives. Other advantages of vacuum interrupters compared to other known interrupters for low-voltage environments include their lower weight and cost, lower maintenance requirements, and longer service life.

Said device further comprises a controllable actuator configured to move said second terminal from said proximal position to said distal position or vice versa; wherein said control module is configured to act on said switch element by means of said controllable actuator. The vacuum switch requires a mechanical action on its second movable terminal to move it to the open or closed position. The use of a controllable actuator allows this mechanical action to be carried out, while the control electronics of the control module are responsible for determining when said action is necessary.

Said controllable actuator comprises:

- a tilting lever, configured to tilt about a tilting axis between a first tilting position and a second tilting position, said lever having a first section on a first side of the axis and a second section on a second side of the axis, opposite said first side;

- actuating means, configured to act on said lever from said second section to move said lever between said first tilting position and said second tilting position, and vice versa;

- fastening means, arranged in said first section, and configured to fasten said lever to said second mobile terminal, such that, in said first tilting position, said second terminal is in said proximal position, and in said second tilting position, said second terminal is in said distal position; and

- locking means, configured to lock said second terminal in said proximal position when said lever is in said first tilting position.

The lever pivots around an axis, and the actuating means moves said lever from one side of the axis. The skilled person will understand that the labels "first section" and "second section" are equivalently interchangeable. The same applies to "first side" and "second side." Thus, when the actuating means moves the lever from one section in one direction, it performs a rocking movement around the axis, moving the other section of the lever in the opposite direction. The holding means hold the second movable terminal, allowing the displacement applied by the actuating means to correspond to a displacement of the second terminal from its proximal position to its distal position, or vice versa. In this way, it is possible to move the vacuum interrupter from a closed state to an open state, or vice versa. In the first pivoting position, the second terminal is in the proximal position and the vacuum interrupter is in a closed state, while in the second pivoting position, the second terminal is in a distal position and the vacuum interrupter is in an open state. The rocker lever arrangement also allows the actuating means to be arranged parallel to the bottle, which provides flexibility to the device design, particularly for use in three-pole fuse-holder bases. Finally, the locking means function to prevent the vacuum interrupter from opening unexpectedly by locking the terminal in its proximal position. Indeed, in cases such as, for example, when a current surge occurs, a force can be induced that tends to separate the electrical contacts inside the vacuum interrupter bottle. If the separation is sufficiently rapid and the distance is large, the main effect is disarming of the vacuum interrupter. However, in other cases, overheating and even melting of said electrical contacts can occur. These effects require subsequent replacement of the damaged device and can lead to hazardous situations. The locking means solve these problems by preventing the electrical connectors from becoming dislodged by preventing the second terminal from moving.

Preferably, said actuating means comprise at least one electromagnet. Each electromagnet is controlled by the control means to apply movement to one side of the lever. This solution does not require additional moving parts such as gears, motors, etc., thus achieving high reliability and longevity. Preferably, two electromagnets are arranged separated by an access space, which facilitates assembly of the device. In particular, the first terminal of the vacuum interrupter can be connected to one of the bars of a three-pole fuse-holder provided at the bottom of said base, which would make assembly of the device difficult in the absence of said access space. In a preferred embodiment, the lever is a flat piece with a C-shaped side, each end of which is actuated by one of said electromagnets, and the interior space leaves said access space free.

Preferably, each of said at least one electromagnet is additionally provided with a permanent magnet, configured to maintain the position of said tilting lever in the event of a loss of power supply to said electromagnet. In this way, the electromagnet only needs to be actuated when it is necessary to move the lever to one or another tilting position. This reduces the device's power consumption and extends its useful life.

Preferably, said manual actuator comprises:

- an actuator rod, arranged in a direction parallel to said second movable terminal of said vacuum switch and movable in said parallel direction, having an end distal to said vacuum switch and an end proximal to said vacuum switch;

- a push button, attached to said actuator stem at said distal end;

said proximal end being mounted attached to said first section of said rocker lever, such that a movement of said manual actuator causes a movement of said lever, and vice versa. In this way, the manual actuator benefits from the arrangement of controllable actuator elements: both are interconnected and the actuation of one affects the other, or vice versa. The effect is that, both by manual actuation and controlled by the control means, it is possible to open and close the switch. Preferably, said manual actuator also comprises a safety device configured to prevent a movement of said manual actuator that entails a movement of said lever from said second rocker position to said first rocker position. This allows an operator to use said safety device to lock the device, for example, in the event that it is necessary to carry out work on the installation: the operator moves the manual actuator, thus moving the lever to its second rocker position and opening the switch, which cuts off the supply to the corresponding electrical branch. The operator then uses the safety lock to lock the device in the open position, ensuring that it cannot be unintentionally returned to the closed position.

Preferably, said fastening means comprise:

- a bushing, integral with said tilting lever, provided with a central through hole traversed by said second terminal and with lateral holes; and

- a pin, arranged across said second terminal and extending perpendicularly thereto and parallel to said tilting axis, passing through said side holes.

The central through-hole is configured with sufficient clearance to allow the second end to pass through it in both the first and second tilting positions. As a preferred example, with a cylindrical second end, the central through-hole has an oval shape with a minor axis parallel to the tilting axis and a major axis perpendicular to it. A similar consideration applies to the side holes and the pin. These configurations with the bushing and pin allow the lever's tilting motion to be converted into a linear motion transmitted to the second end, necessary to move said end between its proximal and distal positions.

Preferably, said locking means comprise:

- a movable part comprising a body provided with a latch on a first side of the body, said movable part arranged to move along a straight line which is perpendicular to said second terminal and to said tilting axis, between a locking position and a release position, or vice versa;

- a spring, attached to said movable part on a second side of the body opposite said first side of the body; and

- a locking hole provided in said bushing, and facing said latch in said first tilting position;

said locking means configured such that, in said first tilting position, when said movable part is in said locking position, said latch is inserted into said locking hole, and said spring is in a working position; and such that, in said release position, said latch is withdrawn from said locking hole and said spring is in a rest position; wherein said body further comprises an upper thrust portion, which has a ramp shape that ascends in the direction of said second terminal, and wherein said tilting lever is provided with a lower thrust portion, which has a ramp shape complementary to said upper thrust portion, configured such that, in said second tilting position, said lower thrust portion is withdrawn from said upper thrust portion and when said lever moves from said second tilting position to said first tilting position, said lower thrust portion pushes said upper thrust portion, causing said movable part to be pulled to said locking position.

Thus, in the released position, the latch is outside the locking hole and the spring is in its resting position. In contrast, in the locked position, the spring is in a working position. In the context of this document, the working position of the spring is understood to be that in which said spring is subjected to a force that elastically deforms said spring. By way of non-exclusive examples, in the case of a tension spring, the working position corresponds to an elongated position, while in the case of a compression spring, the working position corresponds to a compressed position. Thus, in said locked position, the spring tends to pull the moving part in the direction corresponding to the spring's resting position, which tends to move the latch away from the hole. This has the effect that, if there is no element pushing the moving part, the spring itself unlocks the locking means, so that the second terminal tends to move toward its distal position to open the switch. On the other hand, when the lever moves from its second tilting position to its first position, the lower thrust portion engages the upper thrust portion provided on the movable part. The complementary ramp shape of both thrust portions has the effect of converting the lever's tilting movement into a linear thrust of the part toward the second terminal. The thrust continues until, once the first tilting position is reached, the latch is inserted into the locking hole and the blocking means prevent the switch from opening. Thus, a linear thrust of the second terminal itself that attempted to move said second terminal toward its distal position would be blocked by the latch and the locking hole. In contrast, movement of the lever toward its second tilting position releases the force exerted by the lower thrust portion of the lever against the upper thrust portion of the movable part, and the spring pulls said movable part to release the latch from the locking hole. The result is a lock that is effective against unwanted openings, but without the need to apply a high amount of energy to lock or unlock. This facilitates manual operation and reduces the energy requirements for operation controlled by the control module.

Preferably, said moving part also comprises:

- a spring rod, having a first end connected to said body on said second side of the body, and a second end opposite said first end; and

- a balloon, attached to said spring rod at said second end;

said spring being arranged around said spring rod, between said balloon and said body; said device further comprising guide stops arranged to limit the movement of said moving part along said straight line; wherein, in said working position, said spring is compressed between said balloon and said guide stops. In this way, the spring works by compression: it is compressed in the working position and expands to its resting position when the moving part moves from the locked position to the released position. Working by compression is advantageous in relation to the durability of the spring; furthermore, the movement is stable since the spring is traversed by a rod-shaped core. Furthermore, the guide stops facilitate the movement of the moving part to be rectilinear and minimize the risk of deviations occurring over time. In addition, additional parts are not necessary to compress the spring in its working position since the guide stops themselves are used for this purpose.

Preferably, said vacuum interrupter is arranged vertically, such that said second movable terminal is arranged vertically, and said fuse is arranged above said vacuum interrupter. In the context of this document, and unless otherwise indicated, the directions will be understood as relative to the attached figures. Fuse bases generally have a limitation imposed on their dimensions, particularly regarding the width of the fuses connected to them. This limitation is usually imposed by the company performing the installation or exists at the regulatory level. The location of the fuse above the interrupter element allows for the use of relatively wide components, which would not comply with this requirement if arranged laterally. In this way, it is possible to replace the current fuses in three-pole fuse bases with devices such as the one of the invention.

The invention also relates to a three-pole fuse holder provided with at least one electrical safety device according to any of the forms described above.

The invention also encompasses other detailed features illustrated in the detailed description of an embodiment of the invention and in the accompanying figures.

Brief description of the drawings

The advantages and characteristics of the invention can be appreciated from the following description in which, without limiting the scope of the main claim, preferred embodiments of the invention are set forth with reference to the figures.

Fig. 1 shows a perspective view of a three-pole fuse holder provided with three safety devices according to an embodiment of the invention.

Fig. 2 shows in isolation a safety device like the one used in the fuse holder base of Fig. 1.

Fig. 3 is a detailed side view of the safety device of Fig. 2, in which the external casing has been removed in order to see the internal elements.

Fig. 4 is a perspective view corresponding to Fig. 3.

Fig. 5 is a detailed perspective view of the same device as in Fig. 4, with the fuse removed. Fig. 6 is a detailed top view of the device in Fig. 5, with the connector extending from the vacuum interrupter removed.

Fig. 7 is a detailed side view of part of the safety device with the switch in the closed position and the toggle lever in the first toggle position. The walls of the vacuum switch have been removed to reveal the internal terminals.

Fig. 8 is a side view equivalent to Fig. 7 but with the switch in the open position and the rocker lever in the second rocker position.

Fig. 9 and Fig. 10 are detailed side views of the safety device of the invention. Fig. 9 shows the tilting lever in the first tilting position and the latch inserted into the locking hole, while Fig. 10 shows the tilting lever in the second tilting position and the latch removed from the locking hole.

Detailed description of some embodiments of the invention

The figures show a first embodiment of the electrical safety device 1 of the invention, as well as a corresponding three-pole fuse holder base 2.

In particular, the device 1 of the invention is configured to be installed in a three-pole fuse-holder base 2 such as that of Fig. 1, in which the base 2 is provided with three of said devices 1. Fig. 2 shows the device 1 in isolation. The device 1 comprises two electrical terminals 101, 102 between which an electrical branch is defined. In the embodiment shown in Fig. 1 and Fig. 2, the device comprises an external housing made of an electrically insulating material. The device 1 comprises a control module 107, arranged in an area of the housing configured to accept said control module 107. The functionality of the control module is described later in this document. Since said external housing prevents the rest of the internal components from being viewed, for the sake of clarity, said external housing has been eliminated in the rest of Figures 3 to 10. Likewise, the figures are simplified representations of the device 1, so they do not show elements such as the internal wiring.

The main internal elements of the device 1 of the invention are shown in Fig. 3 and Fig. 4. In particular, the figures show how the branch defined between the two terminals 101, 102 is provided with a fuse 103 intended to interrupt the flow of electric current in said branch in the event of a meltdown. In the example, it is a blade fuse with a nominal current value of 400 A, although in other embodiments of the device 1, fuses with other current values are used, adapted to the type of application for which the safety device 1 is intended.

The device 1 further comprises a switching element 104, provided in the branch and connected in series with the fuse 103. The switching element 104 of the example is a vacuum interrupter 150 with nominal values of 400 A, 440 V and 25 kA effective short-circuit at 1 second. The vacuum interrupter 150 has a closed state in which it allows the passage of electric current, and an open state in which it prevents the passage of electric current. Thus, the current passes through the branch if both the fuse 103 and the vacuum interrupter 150 allow the passage. This type of vacuum interrupter 150 is known, so only the most relevant elements for understanding the invention are described. The vacuum interrupter 150 of the example comprises a cylindrical bottle 155 and is represented vertically in the figures. Inside said bottle 155 are two electrical contacts 151, 152 arranged in a vacuum medium. From the upper and lower ends of the bottle 155, two terminals 153 and 154 extend from the central axis of the bottle 155. A first terminal 153 is fixed while the second terminal 154 is mobile and can move vertically in a direction that coincides with the axis of the bottle 155 and that is perpendicular to an outer surface of said bottle 155, in the example of the figures, said outer surface is the upper surface of the bottle 155. Thus, the second terminal 154 can move vertically between a proximal position, in which the electrical contacts 151, 152 of the interior of the bottle 155 are in electrical contact and the vacuum switch 150 is in a closed state, and a distal position, in which the electrical contacts 151, 152 are separated and said vacuum switch 150 is in said open state.

In the case of the first exemplary embodiment, the terminals 153 and 154 are provided with screws so that they can be connected to conductive bars, although other equivalent forms of connection are possible, for example, a soldered connection. The first terminal 153 is connected to an electrical terminal 102 of the device 1, while the second terminal 154 is connected to the fuse 103 by means of a C-shaped section of conductive copper bar that gives it sufficient flexibility to absorb vertical movements of the second terminal 154. As can be seen in Figs. 3 and 4, the vacuum interrupter 150 is arranged vertically, such that the second movable terminal 154 is arranged to be movable in a vertical direction, and the fuse 103 is arranged above said vacuum interrupter 150.

In Fig. 3 and 4 it is shown how the safety device 1 also comprises measuring means, in this case, a first annular current transformer 106, arranged surrounding an electrical conductor of said branch that runs from the fuse 103 to one of the electrical terminals 101 of the device 1. This annular transformer 106 is configured to measure at least one operating parameter of the safety device 1. In the case of the example, said parameter is a measurement of the current circulating through the branch. For the sake of clarity, the electrical connections between the annular transformer 106 and the control module 107 have not been shown in the figures. Said control module 107 is configured to carry out a disarming of the device 1 in the event that the operating parameter, in this case the current measurement, meets a predetermined condition. For the first embodiment, a selector provided in the device 1 allows an operator to predetermine a threshold current value within the range of 160-400 A. In the particular case of the first embodiment, said selector is a potentiometer connected to the control module 107, although other equivalent forms may be provided. In this way, the predetermined condition is that the electric current measurement exceeds said selected threshold current for a threshold time of 0.1 second. The disarming carried out by the control module 107 comprises acting on the switching element 104, in this case the vacuum interrupter 150, to cause said switching element 104 to pass from the closed state to the open state.

In Fig. 5, the device 1 is shown without the fuse 103 and the measuring means 106 so that other components can be seen more clearly. As shown in the figure, the device 1 further comprises a manual actuator 105 comprising an actuator rod 110 and a push button 111. The actuator rod 110 is arranged in a vertical direction, parallel to the second movable terminal 154 of the vacuum switch 150, and is movable in said direction. It has a distal end, remote from the vacuum switch 150, and a proximal end, close to the vacuum switch 150. The push button 111 is secured to the actuator rod 110 at its distal end. The manual actuator 105 is configured to cause the switch element 104 to pass from the closed state to the open state and vice versa. The manner in which this opening and closing of the switch element 104 is carried out by the manual actuator 105 in the first embodiment is described later.

Fig. 5 also shows that the device 1 further comprises a controllable actuator. Said controllable actuator is configured to move the second movable terminal 154 of the vacuum interrupter 150 corresponding to the interrupting element 104 from its proximal position to its distal position or vice versa. In turn, the control module 107 is configured to act on the interrupting element 104 by means of said controllable actuator. The controllable actuator comprises a rocker lever 160, which for the first embodiment is a flat piece with a C-shaped side. Fig. 6 shows a detailed top view in which the arrangement of the rocker lever 160 can be seen, which is configured to rock around a rocking axis 161 between a first rocking position and a second rocking position. In Fig. 5 and Fig. 6, said rocking axis 161 is represented as a dashed line superimposed on the figure. The lever 160 has a first section 162 on a first side of the axis 161 and a second section 163 on a second side of the axis 161, opposite said first side. The proximal end of the actuator rod 110 of the manual actuator 105 is mounted attached to the first section 162 of the lever 160, such that a movement of said manual actuator 105 causes a movement of the lever 160, and vice versa. The controllable actuator also comprises actuating means 170, configured to act on said lever 160 from the second section 163 to move said lever 160 between the first tilting position and the second tilting position, and vice versa. In the case of the embodiment described here, the actuating means 170 comprise two electromagnets 171 separated by an access space 172 that vertically coincides with the free space left by the C shape of the tilting lever 160. Thus, each of the two ends of the second section 163 of the lever 160 is actuated by one of said electromagnets 171, leaving the access space 172 free, which allows access from above to the anchoring point of the lower electrical terminal 102 of the device 1. Each electromagnet 171 is additionally provided with a permanent magnet, configured to maintain the position of said tilting lever 160 in case of loss of electrical supply to said electromagnet 171.

The controllable actuator also comprises holding means 180, arranged in the first section 162 of the lever 160, and holding said lever 160 to the second movable terminal 154 of the vacuum switch 150. In this way, in the first tilting position, the second terminal 154 is in the proximal position, and in the second tilting position in which the vacuum switch 150 is closed, the second terminal 154 is in the distal position in which the vacuum switch 150 is open. In the embodiment of the figures, the fastening means 180 comprise a bushing 181, integral with the tilting lever 160, and provided with a central through hole 182 traversed by the second terminal 154. Fig. 7, 8, 9 and 10 shows how the bushing 181 has ellipsoidal-shaped lateral holes 183. A pin 184 is arranged traversing the second terminal 154 and the bushing 181, up to its lateral holes 183. In particular, the pin 184 extends perpendicular to the second terminal 154 and parallel to the tilting axis 161.

Fig. 7 and Fig. 8 are detailed side views of device 1. To facilitate understanding of the operation of vacuum switch 150, in said figures the walls of said vacuum switch 150 and of the bottle 155 have been removed so that the internal elements are visible. Fig. 7 corresponds to device 1 with the rocker lever 160 in the first rocker position, whereby the second terminal 154 is in the proximal position and the switch element 104 is closed. On the other hand, in Fig. 8 the rocker lever 160 is in the second rocker position, whereby the second terminal 154 is in the distal position and the switch element 104 is open. In Fig. 7 and 8 the two electrical contacts 151 and 152 of the vacuum switch 150 can be seen, which are actually arranged in a vacuum medium inside the bottle 155, but which have been made visible in these figures by removing said bottle 155. The first fixed terminal 153 is connected to a first fixed rod, which communicates with the interior of said bottle 155 and is connected to one of said electrical contacts 151. The second mobile terminal 154 is connected to a second mobile rod, which communicates with the interior of said bottle 155 and is connected to the other of said electrical contacts 152. In this way, when the second terminal 154 is in a proximal position, as in Fig. 7, the electrical contacts 151, 152 are in contact and the vacuum switch 150 is in a closed state, allowing the passage of electrical current. However, when the second terminal 154 is in the distal position, as in Fig. 8, the electrical contacts 151, 152 are separated and the vacuum interrupter 150 is in the open state, preventing the passage of electrical current through it.

Fig. 9 and Fig. 10 are detailed views of the junction area between the second terminal 154 and the rocker lever 160. Fig. 9 corresponds to device 1 with the switch element 104 closed, while Fig. 10 corresponds to device 1 with the switch element open. In said figures it can be seen how the controllable actuator also comprises locking means that are configured to lock the second terminal 154 in the proximal position when the lever 160 is in the first rocker position, which corresponds to the situation shown in Fig. 9. In particular, said locking means comprise a movable part 190 with a body 191 provided with a latch 192 on a first side of the body 191, which in the figures has been represented on the right side. The movable member 190 is mounted so as to move along a straight line that is perpendicular to the second terminal 154 and to the tilt axis 161, and which corresponds to a horizontal line in the figures. The movable member 190 is shown in a locked position in Fig. 9, and in a released position in Fig. 10. The movable member 190 is movable between both positions. Furthermore, the movable member 190 is connected to a spring 196 on a second side of the body 191 opposite the first side of the body, and which corresponds to the left side in the figures. A locking hole 193 is provided in the sleeve 181 of the fastening means 180, which locking hole 193 faces the latch 192 in the first pivoted position shown in Fig. 9. In the situation shown in that figure, the latch 192 is inserted into the locking hole 193. In Fig. 9, the tip of the latch 192 and the locking hole 193 are shown by broken lines, since they would otherwise be hidden in the detailed side view. Furthermore, in Fig. 9, the spring 196 is in a working position which, in the case of the first embodiment, corresponds to a compressed position. However, in the situation shown in Fig. 10, in which the lever 160 is in the second tilting position, and the movable part 190 is in the release position, the latch 192 is withdrawn from the locking hole 193 and the spring 196 is in a rest position.

In Figs. 9 and 10 it is shown that the movable part 190 further comprises a spring rod 198 and a balloon 199. The spring rod 198 is connected to the body 191 at its first end, shown on the right, and to the balloon 199 at its second end, shown on the left. Thus, the spring 196 is arranged around the spring rod 198, between the balloon 199 and the body 191 of the movable part 190. Furthermore, for the first embodiment, the movable part 190 is arranged within a box-shaped guide structure 120. The walls of said guide structure 120 appear as a sectional view in Fig. 9 and 10. Guide stops 197 are formed inside said guide structure 120, in the form of internal walls perpendicular to the direction of movement of the movable part 190. These guide stops 197 limit the movement of the movable part 190 along the horizontal line perpendicular to the second terminal 154, preventing lateral movements. The guide stops 197 close to the spring 196 also serve to compress the spring 196 between said guide stops 197 and the balloon 199, when said spring 196 is in the working position shown in Fig. 9.

In Figs. 9 and 10 it can be seen that the body 191 of the movable part 190 also comprises an upper thrust portion 194, which has a ramp shape that ascends in the direction of said second terminal 154, towards the right in the figures. On the other hand, the tilting lever 160 is provided with a lower thrust portion 195, which has a ramp shape complementary to the upper thrust portion 194 of the movable part. In Fig. 10 it is shown that, in the second tilting position of the lever 160, the lower thrust portion 195 of the lever 160 is withdrawn from the upper thrust portion 194 of the movable part 190. In this situation, the spring 196 tends to expand to its rest position, dragging the movable part 190 and withdrawing the latch 192 from the locking hole 193, as shown in Fig. 10. When the lever 160 moves from the second tilting position shown in Fig. 10 to the first tilting position shown in Fig. 9, the lower thrust portion 195 contacts the upper thrust portion 194 and begins to push it. The shape of the ramps results in the presence of a horizontal component of the drag force that goes in the direction of the second terminal 154, represented on the right in the figures. In this way, the movable part 190 is pulled to the locked position in which the latch 192 is inserted into the locking hole, as shown in Fig. 9. When the device 1 is in this position, any vertical thrust of the second terminal 154 will be blocked by the interaction of the latch 192 with the lower wall of the locking hole 193, thus producing a safety closure. On the other hand, a movement carried out on the tilting lever 160, for example, by the actuation of the electromagnets 171 or the manual actuator 105, separates the lower thrust portion 195 connected to the lever 160 from the upper thrust portion 194 of the movable part, and the spring 196 itself pushes the movable part 190 towards the position shown in Fig. 10. Therefore, the locking only affects movements initiated by the vertical displacement of the second terminal.

Other embodiments of the safety device 1 that share many of the characteristics of the first embodiment described above are described below. Therefore, only the differentiating elements will be described below.

In a second embodiment, not shown in the figures, the device 1 further comprises a second annular current transformer, configured to electrically supply said control module 107 and said electromagnets 171.

In a third embodiment, the operating parameters comprise a measurement of electric current in the branch, and the predetermined condition corresponds to the situation in which said measurement of electric current exceeds a threshold current without taking into account the time in which said threshold is exceeded.

In a fourth embodiment, the operating parameter additionally comprises a temperature measurement.

In a fifth embodiment, said operating parameter additionally comprises a voltage measurement. Still other embodiments utilize an operating parameter comprising current, voltage, and temperature measurements.

In a sixth embodiment, the control module 107 is further configured to perform a reset, which comprises acting on said switch element 104 to cause said switch element 104 to transition from said open state to said closed state. The control module 107 initiates the reset when a predetermined reset time has elapsed since said disarming, which is a variable value between 5 and 180 seconds. In addition, the control module 107 is configured to perform up to 5 retries in the event that a disarming occurs immediately after said reset.

In a seventh embodiment, the control module 107 further comprises a transmitter and a receiver configured to send operating parameters and receive commands. The commands include configuration commands, disarm initiation, and reset initiation. In some embodiments, the reset initiation command includes the predetermined retry values. Some examples of configuration commands include changing the predetermined condition, changing the predetermined reset time, or changing the number of retries.

Claims (15)

1. Electrical safety device (1) configured to be installed in a three-pole fuse holder base (2), comprising two terminals (101, 102) between which an electrical branch is defined, said branch being provided with a fuse (103) configured to interrupt the passage of electrical current in said branch in case of fusion; wherein said device (1) further comprises: - a switching element (104), provided in said branch and connected in series with said fuse (103), said switching element (104) having a closed state in which it allows the passage of electric current, and an open state in which it prevents the passage of electric current; - a manual actuator (105), configured to cause said switch element (104) to pass from said closed state to said open state and vice versa; - measuring means (106), configured to measure at least one operating parameter of said safety device (1); and - a control module (107), configured to carry out a disarming in the event that said at least one operating parameter meets a predetermined condition, wherein said disarming comprises acting on said switch element (104) to cause said switch element (104) to pass from said closed state to said open state; wherein said device (1) further comprises a controllable actuator, and said control module (107) is configured to act on said switching element (104) by means of said controllable actuator; characterized in that said switching element (104) comprises a vacuum switch (150), of the type comprising: - a bottle (155) in which two electrical contacts (151, 152) are provided, arranged in a vacuum medium; - a first fixed terminal (153), connected to a first fixed rod, which communicates with the interior of said bottle (155) and is connected to one of said electrical contacts (151, 152); - a second mobile terminal (154), connected to a second mobile rod, which communicates with the interior of said bottle (155) and is connected to the other of said electrical contacts (151, 152); wherein said second terminal (154) is movable in a direction perpendicular to said bottle (155) between a proximal position, in which said electrical contacts (151, 152) are in contact and said vacuum switch (150) is in said closed state, and a distal position, in which said electrical contacts (151, 152) are separated and said vacuum switch (150) is in said open state; said controllable actuator configured to move said second terminal (154) from said proximal position to said distal position or vice versa; said controllable actuator comprising: - a tilting lever (160), configured to tilt around a tilting axis (161) between a first tilting position and a second tilting position, said lever (160) having a first section (162) on a first side of the axis (161) and a second section (163) on a second side of the axis (161), opposite said first side; - actuating means (170), configured to act on said lever (160) from said second section (163) to move said lever (160) between said first tilting position and said second tilting position, and vice versa; - fastening means (180), arranged in said first section (162), and configured to fasten said lever (160) to said second mobile terminal (154), such that, in said first tilting position, said second terminal (154) is in said proximal position, and in said second tilting position, said second terminal (154) is in said distal position; and - locking means, configured to lock said second terminal (154) in said proximal position when said lever (160) is in said first tilting position. 2. Device (1) according to claim 1, characterized in that said control module (107) is additionally configured to carry out a reset, which comprises acting on said switch element (104) to cause said switch element (104) to pass from said open state to said closed state; preferably, said control module (107) is additionally configured to initiate said reset when a predetermined reset time has elapsed since said disarming. 3. Device (1) according to claim 2, characterized in that said control module (107) is additionally configured to carry out at least one retry in the event that immediately after said rearming a disarming occurs, the total number of retries being preferably limited to a predetermined value of retries. 4. Device (1) according to any one of claims 1 to 3, characterized in that said operating parameters comprise a measurement of electric current in said branch, and said predetermined condition comprises at least one of the conditions where: - said electric current measurement exceeds a threshold current; and - said electric current measurement exceeds a threshold current for a threshold time; preferably, wherein said measuring means (106) comprise a first annular current transformer, arranged surrounding an electrical conductor of said branch. 5. Device (1) according to any of claims 1 to 4, characterized in that it further comprises a second annular current transformer, configured to electrically supply said control module (107). 6. Device (1) according to any one of claims 1 to 5, characterized in that said operating parameters additionally comprise at least one of: - a measure of temperature; - a current measurement; and - a measurement of voltage. 7. Device (1) according to any of claims 1 to 6, characterized in that said control module (107) further comprises remote connection means, configured for at least one of: - sending said operating parameters; and - receiving commands. preferably, in which said commands comprise at least one of: - a configuration order; - an order to begin such disarmament; and - an order to begin such rearmament; wherein preferably, said order to initiate said rearm comprises said predetermined retry value; more preferably, wherein said configuration order comprises at least one of: - an order to modify said predetermined condition; - an order to modify said predetermined reset time; and - an order to modify said default value of rearm retries. 8. Device (1) according to any one of claims 1 to 7, characterized in that said actuating means (170) comprise at least one electromagnet (171), preferably two electromagnets (171) separated by an access space (172). 9. Device (1) according to claim 8, characterized in that each of said at least one electromagnet (171) is additionally provided with a permanent magnet, configured to maintain the position of said tilting lever (160) in case of loss of electrical supply to said electromagnet (171). 10. Device (1) according to any of claims 1 to 9, characterized in that said manual actuator (105) comprises: - an actuator rod (110), arranged in a direction parallel to said second mobile terminal (154) of said vacuum switch (150) and movable in said parallel direction, having an end distal to said vacuum switch (150) and an end proximal to said vacuum switch (150); - a push button (111), attached to said actuator rod (110) at said distal end; said proximal end being mounted attached to said first section (162) of said tilting lever (160), such that a movement of said manual actuator (105) causes a movement of said lever (160), and vice versa. 11. Device (1) according to any one of claims 1 to 10, characterized in that said fastening means (180) comprise: - a bushing (181), integral with said tilting lever (160), provided with a central through hole (182) traversed by said second terminal (154) and with lateral holes (183); and - a pin (184), arranged passing through said second terminal (154) and extending perpendicularly thereto and parallel to said tilting axis (161), passing through said side holes (183). 12. Device (1) according to claim 11, characterized in that said locking means comprise: - a movable part (190) comprising a body (191) provided with a latch (192) on a first side of the body, said movable part (190) arranged to move along a straight line which is perpendicular to said second terminal (154) and to said tilting axis (161), between a locking position and a release position, or vice versa; - a spring (196), connected to said movable part (190) on a second side of the body opposite said first side of the body; and - a locking hole (193) provided in said bushing (181), and facing said latch (192) in said first tilting position; said locking means configured such that, in said first tilting position, when said movable part (190) is in said locking position, said latch (192) is inserted into said locking hole (193), and said spring (196) is in a working position; and such that, in said release position, said latch (192) is withdrawn from said locking hole (193) and said spring (196) is in a rest position; wherein said body (191) further comprises an upper thrust portion (194) having a ramp shape that rises in the direction of said second terminal (154), and wherein said tilting lever (160) is provided with a lower thrust portion (195) having a ramp shape complementary to said upper thrust portion (194), configured so that, in said second tilting position, said lower thrust portion (195) is withdrawn from said upper thrust portion (194) and when said lever (160) moves from said second tilting position to said first tilting position, said lower thrust portion (195) pushes said upper thrust portion (194), causing said movable part (190) to be pulled to said locking position. 13. Device (1) according to claim 12, characterized in that said movable part (190) further comprises: - a spring rod (198), having a first end connected to said body (191) on said second side of the body, and a second end opposite said first end; and - a balloon (199), connected to said spring rod (198) at said second end; said spring (196) being arranged around said spring rod (198), between said balloon (199) and said body (191); said device (1) further comprising guide stops (197) arranged to limit the movement of said movable part (190) along said straight line; in which, in said working position, said spring (196) is compressed between said balloon and said guide stops (197). 14. Device (1) according to any one of claims 1 to 13, characterized in that said vacuum switch (150) is arranged vertically, such that said second movable terminal (154) is arranged movably in a vertical direction, and wherein said fuse (103) is arranged above said vacuum switch (150). 15. Three-pole fuse holder base (2) provided with at least one electrical safety device (1) according to any of claims 1 to 14.