WO2017017302A1

WO2017017302A1 - Switch based on a variable magnetic field

Info

Publication number: WO2017017302A1
Application number: PCT/ES2016/070561
Authority: WO
Inventors: Jorge Torre Sarmiento
Original assignee: Jorge Torre Sarmiento
Priority date: 2015-07-24
Filing date: 2016-07-22
Publication date: 2017-02-02
Also published as: ES2603410B1; ES2603410A1

Abstract

The invention relates to a device comprising: a casing (1); an encapsulated magnetic reed switch (2) disposed inside the casing and comprising contact terminals (4, 5) connected to corresponding electroconductive wires (6, 7); a first permanent magnet (8); and a second permanent magnet (9). The permanent magnets (8, 9) generate respective magnetic fields (3) and (10) which surround the capsule of the reed switch (2). The first (8) and second (9) permanent magnets are aligned and centred on the longitudinal geometric axis of the reed switch. The first (8) and second (9) permanent magnets are situated at a determined distance from the reed switch according to their magnetic properties and the sensitivity of the switch. The first (8) and second (9) magnets are disposed in positions opposite the reed switch, such that the magnets (8, 9) generate respective stable and balanced magnetic fields (3, 10) that surround the capsule of the reed switch (2) and maintain the connection between the contact terminals (4, 5) of the reed switch in a stable open or closed position.

Description

Variable magnetic field switching device

Field of the invention

The present invention is encompassed within the general field of electronics, magnetism and safety, and particularly in the systems or devices of action by means of the action of forces or magnetic or electromagnetic fields, used for the opening or closing of electrical circuits or electronic, said drive devices being connected to the corresponding circuit by means of electroconductive wires, Background of the invention

The magnetic type switches are widely known in the state of the art, having multiple applications according to their design and functionality. Almost all of them are based on the use of the magnetic field to activate or deactivate a mechanical type switch. An example of a magnetic contactor can be found in the type known as "reed switch", developed in 1936 by WB Elwood; It consists of two ferromagnetic filaments coated with rhodium or iridium, separated from each other and hermetically sealed in a glass tube or plastic encapsulation, which is filled with an inert gas in order to prevent sparks from forming in the contacts. The "reed switch" is activated by the action of the magnetic field of an energized coil or a permanent magnet that induces the North and South poles in the contacts, causing them to join by closing the circuit, initially open. When the magnetic field is removed, the elasticity of the contacts causes the circuit to open again. The external ends of the switches are joined or soldered to respective electroconductive wires of the circuit to which they are coupled, which when closing the circuit allows the transmission of the corresponding signal to an electrical or electronic system. There are other more modern switches or magnetic switches that, without requiring a "switch" (or switch) encapsulated type "reed", involve the movement of a piece carrying a permanent magnet that drives a "switch" or switch conventional due to the proximity of a ferric body due to the attraction to said ferrous surface by the magnetic field of a permanent magnet. A device of this type is used in ES 1 061 308 U. The first devices mentioned are used in many fields of technology, from intrusion detectors in security installations, to position indicators of certain machines or devices where the movements of parts Mechanical failures can lead to breakdowns if conventional wiring systems or switches are used. The second system has a less generalized use, but has the advantage of being able to activate loads of the desired power since it adapts to any type of switch, something that does not happen with the encapsulated switches, or when it is achieved, the dimensions of the equipment become extremely bulky.

The systems described, although practical in some of their utilities, present several drawbacks, especially in the field of security, as they are easily vulnerable. The "reed" switches work in the proximity of a magnetic field produced by a permanent magnet or a coil, and precisely their own operating characteristics require that they consist of two well-defined parts, on the one hand a capsule containing the "switch" switch, and on the other a second capsule that contains the permanent magnet, which must face each other for the system to activate. This can be seen in access facilities to protected places, such as doors and windows. The size of these elements and their own operation requires that these facilities are made in highly visible places and within reach of anyone. Mechanical switches, such as the one described in ES 1 061 308 U, which operate in the proximity of a ferrous surface or a permanent magnet whose pole is the opposite of the end of the mobile contactor, can be made with more or less reduced sizes and can be retracted more easily than the previous ones, since in one of its ends it only needs a ferric metal sheet. However, both systems have the same drawbacks in terms of security applications since they can be very easily screened, which means that the secured accesses are completely vulnerable to intruders. In the first one, it will be enough to bring a permanent magnet towards the place where the encapsulated "reed", so that the magnetic force exerted by the intruder magnet is added to the magnetic force of the magnet that supports it, and in this way the door or window that contains the encapsulated magnet can be opened, without being detected by the system of alarm, which will remain armed.

In the second case it will also be sufficient to approach a magnet or a ferromagnetic material to the place occupied by the mechanical detector, to maintain its fixed position, and in this way it will be possible to act as in the previous case, being much easier to detect the device due to the sound it produces when activated or deactivated.

These effects are produced by the activity of the dipolar magnetic field that a single magnet exerts, in the first case, on the terminals of the "reed switch", and in the second, on a metal sheet.

Description of the invention

The present invention not only solves the aforementioned drawbacks but also opens a range of new technological applications related to magnetic activity and applications from the point of view of mechanics, providing important novelties and advantages over the current state of the art.

It describes a device that, taking advantage of the technology provided by the "reed switch", and the operating principles of the mechanical magnetic connector described by ES 1 061 308 U, consists essentially of a switch "reed switch" at whose ends and at a distance depending on the calibration you want to give the switch and the size of the "reed", will be placed both permanent first and second magnets, whose centers of balance between North and South, should be perfectly aligned with the center of the axis of each terminal of the "reed switch", but polarized in opposition, that is, at one end, the north side of the first magnet must be oriented in the opposite direction to that of the second magnet on the opposite side, and vice versa. In this way, the magnetic state of the "reed switch" will produce a repulsive force with the magnets facing opposite in equilibrium condition, and both this repulsive force will produce the separation of the contact terminals of said "reed switch" when said magnetic repulsion force is greater than the mechanical elastic tension tending to the closing of the "reed switch". In such conditions the circuit will remain open by the magnetic force of repulsion due to the action of the opposing magnetic fields against the mechanical tension of the "reed switch" tending to its closure. When a disturbing element of the magnetic balance is applied in the "reed switch", such as a permanent magnet, a coil, or a ferromagnetic element, the repulsion force in the switch zone will also be altered, so that said force is reduced of repulsion, which will allow the closure of the "reed switch" circuit.

This device also allows great flexibility in terms of working parameters, as well as almost infinite calibration factors, as it can be adjusted by the sensitivity of the "reed switch", the work direction or objective detection, the separation distance between both magnets, the factor or index of magnetic induction thereof, and their difference in size, which can provide numerous models depending on the desired application.

In addition to the drive from the front of the device, the device can also be configured so that the drive is performed from one of the ends, achieving the same effect as described above, but with a configuration that allows the realization of a cylindrical type switch of very small dimensions, and of greater security than the previous one, since it allows to work using permanent magnets at a greater distance, and therefore a magnetic field effect in equilibrium much more sensitive.

Finally, placing at each end of the "reed switch" two permanent magnets polarized in magnetic attraction, the inverse effect is achieved, ie the circuit in the "reed switch" will remain normally closed until a magnet approaches. polarization in opposition, that is to say in repulsion, which will cause the opening of the circuit; However, it may be the case that due to the action of a sufficiently intense magnetic field and close to the device, a new magnetic field surround and attraction between the ends of the "reed switch" which will cause the forced closure of the circuit, generating in turn a strong screening on the "reed switch" that prevents its permanent change of state until it occurs a mechanical movement that separates both parts, this embodiment being constituted as the safest from the point of view of a possible intrusiveness.

Any of the three described configurations, in which essentially what is generated around the "reed switch" is a magnetic field permanently in equilibrium, gives rise to a state of connection or disconnection that can be detected by an external system, as a Ferromagnetic material, or a permanent magnet, is approximated slightly towards the place occupied by the "reed", making it impossible to shield it due to the distortion of the magnetic field in equilibrium, and the consequent opening or closing of the "reed switch".

In short, the device object of the present invention, in addition to offering numerous advantages in terms of the current state of the art in security, opens new possibilities and expectations for multiple industrial applications where a switch or high security switch of extremely large size is required. reduced and simple construction, which can be completely sealed, and which can work at different temperatures depending on the technical characteristics of the dipole elements used and those of the "reed switch" itself, which gives it a very high degree of reliability, for example, in the field of the automotive industry, robotics, home automation, toy, aeronautics, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to illustrate the explanation that will follow, we enclose three sheets of drawings, in which eight figures represent, by way of example and without limitation, the essence of the present invention, and in the that can be observed:

Figure 1 shows a schematic view of a first embodiment of the switch device by magnetic field variable of the invention with actuation from a front part to the "reed switch", in a state of rest with the circuit open;

Figure 2 shows a schematic view of the example of figure 1, in the actuation state with the closed circuit;

Figure 3 shows a schematic view of a second embodiment of the variable magnetic field switching device of the invention with activation from one of its ends, in a state of rest with the open circuit;

Figure 4 shows a schematic view of the example of figure 3, in the actuated state by a ferromagnetic body, with the circuit closed;

Figure 5 shows a schematic view of the example of figure 3, in the actuation state by a permanent magnet with serial polarity, with the circuit closed;

Figure 6 shows a schematic view of the example of figure 3, in which the drive comprises an additional magnet with opposite polarity to that shown in figure 5, with the circuit closed;

Figure 7 shows a schematic view of a second example of embodiment of the variable magnetic field switching device of the invention with activation from one of its ends, in a state of rest with the closed circuit; Y

Figure 8 shows a schematic view of the example of figure 7, in the actuated state with the open circuit.

Description of the preferred embodiments

A first embodiment of the invention relates to a variable field magnetic switching device, comprising:

• a housing (1);

· An encapsulated switch reed switch (2) disposed inside said casing, and which is sensitive to the strength of any magnetic field, and which it is provided with contact terminals (4,5), at the ends of which are connected electroconductive wires (6,7);

• a first permanent magnet (8);

• a second permanent magnet (9);

· A drive zone located between the permanent magnets (8,9);

wherein the first (8) and second (9) permanent magnets are aligned and centered on the longitudinal axis of the "reed switch";

wherein the neutral line or plane between the poles is arranged along the longitudinal axis of the "reed switch";

wherein the permanent magnets first (8) and second (9) are located at a certain distance from the "reed switch" according to their magnetic properties, normally being equal magnetic properties and being arranged at equal distances from the "reed switch";

wherein the first (8) and second (9) magnets are arranged symmetrically in opposite positions with respect to the "reed switch"; Y

wherein the first (8) and second (9) magnets are oriented in magnetic opposition;

so that said magnets generate respective magnetic fields, balanced and stable (3, 10) around the capsule of the reed switch (2), which prevents the connection of the contact terminals (4,5).

The operation according to this first embodiment is as follows:

When a distortion source is approached to the housing (1) containing the reed switch (2), such as a ferromagnetic material (11) or a permanent magnet (12), and particularly to the driving area aligned between the poles exposed North or South of the permanent magnets (8,9), the existing balance is disturbed in rest state and a new combined magnetic field (13) is generated by induction, so that the repulsion forces in the terminals are eliminated ( 4,5) which allows the mechanical tension of the "reed switch" to produce the approximation of the contact terminals (4,5) and the closing of the circuit.

By removing the distortion source of the switching device of the invention, the permanent magnets (8,9) will return to their condition and return to the condition of equilibrium the original magnetic fields (3,10), producing again the repulsion between the terminals (4, 5) and the opening of the circuit.

Additionally, when acting on the switch reed switch (2) an induced magnetic field (13) that keeps it in a closed condition, that is, with the terminals (4,5) joined together, when approaching the switch reed switch ( 2) a new magnet (15) or a ferromagnetic material (16), whose induction factor is equal to or greater than the magnetic force exerted by the ferromagnetic material (11) or equal, greater or less than the permanent magnet (12), a distortion will occur in the equilibrium state of the induced magnetic field (13), with respect to the reed switch (2), thus determining a change of state in the reed switch (2) given by the difference of the force vectors of the magnetic fields acting on the terminals (4,5) of the reed switch (2). A second embodiment of the invention relates to a variable field magnetic switching device similar to that of the first embodiment, in which the actuation takes place at one of its ends. In particular it comprises:

• a housing (1);

• an encapsulated reed switch (2) contained in said casing (1), sensitive to the force of any magnetic field, at the ends of its contact terminals (4,5) connecting electroconducting wires

(6,7);

a first permanent magnet (8);

a second permanent magnet (9);

a drive zone located at the end of one of the permanent magnets (8,9)

wherein the first (8) and second (9) permanent magnets are aligned and centered on the longitudinal axis of the "reed switch"; wherein the neutral line or plane between the poles is arranged perpendicularly to the longitudinal axis of the "reed switch";

wherein the first (8) and second (9) permanent magnets normally have the same magnetic properties; in which the first (8) and second (9) permanent magnets are located at a certain distance from the "reed switch" according to their magnetic properties;

wherein the first (8) and second (9) magnets are arranged symmetrically in opposite positions with respect to the "reed switch",

so that said magnets generate respective magnetic fields, balanced and stable (3.10) around the capsule of the reed switch (2), which prevents the connection of their corresponding contact terminals (4,5); and so that the magnetic repulsion forces separate the contact terminals (4,5) from the "reed switch" (2), which in the rest position are kept separated in the open circuit position. The mode of operation according to this second embodiment, the operation is as follows:

When approximating a ferromagnetic material (11) or a permanent magnet (12) to the drive zone of the housing (1) containing the reed switch (2), and particularly aligned to one of the poles exposed North or South of the permanent magnets (8,9), an additional magnetic field is produced (34,37 according to orientation of the respective polarities) that due to its proximity to the reed switch (2) causes an imbalance in the state of the magnetic fields (3, 10), reducing or eliminating the repulsive force in the contact terminals (4,5), which contact each other;

When removing the source of distortion, ie the ferromagnetic material (11) or the permanent magnet (12), the additional magnetic field (34) will stop acting on the system so that the magnetic fields (3,10) generated by the first and second permanent magnets will be balanced, recovering the magnetic force of repulsion, and consequently the separation of the contact terminals will take place, so that the "reed" switch will go back to its open circuit condition. Additionally, when acting on the switch reed switch (2) an induced magnetic field (34) that keeps it in the closed position, that is, joined the contact pins (4,5), when approaching the switch reed switch (2) ), an additional magnet or an additional ferromagnetic material, whose magnetic density is equal to or greater than the magnetic force exerted by the ferromagnetic material (11) or equal to, greater or less than the permanent magnet (12), a change in the induced magnetic field (34), and consequently in the position of the contact terminals (4,5) and a change in the state of the "reed switch" (2). This second embodiment involves a third state, which will be dependent on the calibration given by the distance between each other and the inductive capacity with which the permanent magnets (8,9) are calibrated with respect to the reed switch (2), in accordance with the greater or lower inductive capacity of the ferromagnetic material on which the device rests, which together determines that the device can be supported on a calculated ferromagnetic material, without the induced magnetic field produced causing a sufficient distortion on the balanced and stable magnetic field ( 3), except when the support of any permanent magnet occurs at a point more or less close to the point of support of the device, distance determined according to the magnetization capacity of the ferromagnetic surface, which gives the ferromagnetic material a field strength in the point of support of the device that causes sufficient distortion of the magnetic field equili bred (3), and consequently the closing of the reed switch (2).

A third embodiment of the invention relates to a variable field magnetic switch device similar to the two previous ones, comprising:

• one housing (1)

• an encapsulated switch "reed switch" (2), arranged in said casing (1), sensitive to the force of any magnetic field, provided with contact terminals (4,5) at the ends of which are connected electroconducting wires

(6,7);

a first permanent magnet (8);

a second permanent magnet (9); • a drive zone located at the end of one of the permanent magnets (8,9);

wherein the neutral line or plane between the poles is arranged perpendicularly to the longitudinal axis of the "reed switch";

wherein the first (8) and second (9) permanent magnets normally have the same magnetic properties;

wherein the first (8) and second (9) permanent magnets are located at a certain distance from the "reed switch" according to their magnetic properties; wherein the first (8) and second (9) magnets are arranged symmetrically in opposite positions with respect to the "reed switch",

wherein the first (8) and second (9) magnets are located with the same magnetic orientation;

so that said magnets generate respective magnetic fields, balanced and stable (3, 10) around the capsule of the reed switch (2), which force the connection of their corresponding contact contact terminals (4,5); and so that magnetic attraction forces hold together the contact terminals (4,5) of the "reed switch" (2), which in the rest position are held together, in the closed circuit position.

According to this embodiment, the operation is as follows:

Approaching the housing (1) container of the reed switch (2), a source of distortion, for example a permanent magnet (12), orienting its North or South pole in repulsion mode with respect to the North or South pole of the magnet ( 8,9) located in the drive zone, centered on the longitudinal axis of the "reed switch" (2), generates an additional magnetic field of repulsion that modifies the state of the balanced magnetic field (3), generating a third magnetic field induced (54) that causes a deviation of the magnetic field affected the permanent magnet (8) or (9) to which the permanent magnet (12) has approached, which causes a change in the polarity state of the "reed switch" (2) that goes into "repulsion mode", opening the circuit as a consequence of the incidence on its contact terminals (4,5) that come to separate.

By removing the distortion source from the stable magnetic field (3), that is, the permanent magnet (12), the additional magnetic field of repulsion will stop acting on the balanced magnetic field (3), and the reed switch will go back to its closed position, due to the effect of the dipolar magnetic fields produced by the permanent magnets (8,9).

This last embodiment provides a higher degree of security than the previous embodiments compared to the approach towards the reed switch (2) of any ferromagnetic element or a new permanent magnet, to try to shield it, given the extreme radial curvature of the magnetic field generated by the approach of the permanent magnet (12) caused by the repulsion effect with respect to the magnet (8,9) it approaches, which will produce a new additional magnetic field that will close the switch "reed switch" (2).

It is provided that the housing (1) has internal housings shaped to receive the corresponding permanent magnets (8,9) therein in the appropriate positions. Said internal housings may have a disk shape, rectangular section, or others, and they shall be arranged in alignment with the "reed switch" axis (2).

Obviously the final form of the device can be diverse, depending on the application, any of the forms falling within the scope of the invention remaining, as long as the technology described herein is used.

Claims

Variable magnetic field switching device, characterized in that it comprises:

• A casing (1);

• An encapsulated magnetic "reed switch" (2) arranged inside said casing, which comprises contact terminals (4,5) connected to corresponding electroconductive wires (6,7);

• A first permanent magnet (8);

• A second permanent magnet (9);

In which said permanent magnets (8,9) generate separate magnetic fields (3) and (10), which act by enveloping the capsule of the "reed switch" (2);

And because the first (8) and second (9) permanent magnets are aligned and centered on the longitudinal axis of the reed switch;

And because the first (8) and second (9) permanent magnets are located at a certain distance from the "reed switch" depending on their magnetic properties and sensitivity of the switch;

And because the first (8) and second (9) magnets are arranged in opposite positions with respect to the "reed switch", so that said magnets (8,9) generate separate, balanced and stable surrounding magnetic fields (3,10) around the reed switch capsule

(2), which maintain the connection between the contact terminals (4,5) of the "reed switch" in a stable open or closed position.

Variable magnetic field switching device, according to claim 1, characterized in that the first (8) and second (9) magnets are arranged with their neutral axis or plane aligned with the longitudinal geometric axis of the reed switch.

3. Variable magnetic field switching device, according to claim 1, characterized in that the first (8) and second (9) magnets are arranged with their axis or neutral plane perpendicular to the longitudinal geometric axis of the reed switch.

4. Variable magnetic field switching device, according to any of claims 1 to 3, characterized in that the first (8) and second (9) magnets are symmetrically arranged in opposite positions with respect to the "reed switch".

Variable magnetic field switching device, according to claim 4, characterized in that the first (8) and second (9) magnets have equal magnetic properties and are arranged at equal distances from the "reed switch" (2).

Variable magnetic field switching device, according to any of claims 1 to 5, characterized in that the first (8) and second (9) magnets are oriented in magnetic opposition, in which the repulsion forces of the respective magnetic fields tend to maintain separate the contact terminals (4,5) of the reed switch and the circuit in the open position; 7. Variable magnetic field switching device, according to any of claims 1 to 5, characterized in that the first (8) and second (9) magnets are arranged with the same orientation on both sides of the "reed switch" (2), in which the attractive forces of the respective magnetic fields tend to keep the contact terminals (4,5) of the reed switch together and the circuit in the closed position.

Variable magnetic field switching device, according to any of claims 1 to 7, characterized in that it comprises a drive device, said drive device being:

• a permanent magnet (12), or

• a plate of ferromagnetic material (11).

Variable magnetic field switching device, according to claim 6, characterized in that it comprises an actuation area through the approximation of the actuation device, said actuation area being arranged in the space between the permanent magnets (8,9). Variable magnetic field switching device, according to claim 6, characterized in that it comprises an actuation area through the approximation of the actuation device, said actuation area being arranged at the end where one of the permanent magnets (8,9) is located. ).

Variable magnetic field switching device, according to any of claims 1 to 10, characterized in that the housing (1) has internal housings with the appropriate shape to receive the corresponding permanent magnets (8,9) in the appropriate positions, being said internal housings in alignment with the geometric axis of the "reed switch" (2).