WO2016151175A1

WO2016151175A1 - Multipole linear power switch

Info

Publication number: WO2016151175A1
Application number: PCT/ES2016/070201
Authority: WO
Inventors: Jose Oscar ANDALUZ SORLÍ
Original assignee: Gorlan Team, S.L.U.
Priority date: 2015-03-25
Filing date: 2016-03-22
Publication date: 2016-09-29
Also published as: EP3073501B1; EP3073501A1; ES2637193T3

Abstract

The invention relates to a multiple power switch device, operated by an actuator having rectilinear movement, for alternately opening and closing the electrical connection of the switch poles. Each switch pole is formed by a mobile contact and two fixed contacts, wherein the mobile contacts are formed as a single plate of contacts having upper and lower surfaces, such that when the switch is in the closed position, only the upper or lower surface of each contact of a mobile plate makes contact with the associated fixed contacts from the first and second groups. The relative position between the mobile contact and the fixed contacts of a pole of the switch alternates from one pole to the adjacent poles. The switch is cheaper and easier to produce, and at the same time is able to efficiently quench electric arcs that originate during transient current interruption and closing operations.

Description

MULTIPOLE LINEAR POWER SWITCH

DESCRIPTION

Object of the invention

The present invention relates in general to electrical switches and / or to circuit switching devices, particularly adapted to extinguish the electric arc generated in the contacts of a switch during the opening and closing operations.

More particularly, the invention relates to a multi-pole electrical switching device operated by a rectilinear motion actuator, to alternatively open and close the electrical connection of the switch poles.

An object of the invention is to provide a multi-pole linear switch that is cheaper and easier to manufacture compared to prior art devices, and at the same time capable of cooling or extinguishing electric arcs that originate during a transient current interruption and closing operations more efficiently.

Background of the invention

Mechanical switches are devices used to connect and disconnect a load from a power source, and are based on the application of an external force that moves several mobile contacts with respect to other fixed contacts, so that when the circuit is going to close, the mobile contacts come into contact with the fixed contacts, forming the connection between the load and a power source thus allowing current flow.

The opposite process corresponds to the movement of the mobile contacts with respect to the fixed contacts, so that these mobile contacts move away from the fixed contacts, causing the circuit to open and thus interrupting the flow of current. European patent application EP-2,667,394 A1 is an example of a multi-pole linear switch. This type of switches is represented in the attached figures 1 A, B for the case of four-pole switches, and comprises a first group of fixed contacts (1 a, 2a, 3a, 4a), a second group of fixed contacts (1c , 2c, 3c, 4c), and a group of mobile contacts (1 b, 2b, 3b, 4b) capable of moving simultaneously between an electric open position and an electric closed position of the switch, such as for each pole of the switch , by connecting a mobile contact electrically a fixed contact of the first group with a fixed contact of the second group. Therefore, each pole of the switch consists of a mobile contact and its associated fixed contacts, for example a first pole is defined by the contacts (1 a, 1 b, 1 c), a second pole is defined by the contacts ( 2a, 2b, 2c) and so on. Each pole can be used to open and close an individual power line of a large detail. Alternatively, as shown in Figure 1, some poles are permanently connected in series to break the flow of current at various cut-off points, to simply extinguish the electric arc.

The group of mobile contacts are mounted with an actuator (5), which is mobile in a rectilinear manner alternately between an open position and a closed position of the switch. As shown in Figures 1 and 2, conventionally these mobile contacts are double plate contacts, so that each mobile contact (1 b, 2b, 3b, 4b) is formed by two overlapping plates (1 b ', 1 b "), (2b ', 2b"), (3b', 3b "), (4b ', 4b"), respectively, as defined as a separation between both plates, in which a contact portion of the fixed contacts Associated is closely inserted in the closed position in contact on two surfaces, respectively, with the two plates, as shown in more detail in Figure 2C.

This double plate configuration has been traditionally used for decades. The reason for this is that with two overlapping plates the contacts better withstand the high short-circuit currents. Since an electric current generates an electromagnetic field, the mobile and fixed contacts are biased separated from each other by the generated electromagnetic field. To compensate for this repulsive force, elastic elements are generally used forcing contacts. mobile and fixed together, otherwise sparks would appear and contact surfaces would deteriorate.

Due to these superimposed plates, the current is distributed equally to each of them in the same direction, so that, due to the electromagnetic fields generated, the superimposed plates are attracted to each other, so that this force of attraction is added to the strength of the electrical elements, to the extent that mobile contacts are able to withstand high short-circuit forces.

Electric arcs or voltaic arcs are formed during transient operations, in the contact areas between the mobile and fixed contacts. Electric arcs are known to cause many problems because the heat generated during an electric arc is highly destructive. Some of these problems are: deterioration of the switch materials, breakdowns and / or total or partial destruction of electrical installations, including damage to people caused by burns or other injuries.

The problems in extinguishing electric arcs are particularly pronounced in the interruption of direct current because, unlike alternating current, there is no zero crossing, so that the electric arcs must be eliminated as quickly as possible by deionizing the medium and increasing the dielectric strength Several techniques are known today for extinguishing electric arcs that form when the contacts of an automatic switch or disconnect the opening and closing switch. The common objective shared by all these techniques is that the energy dissipated in the heat of the electric arc be as small as possible, with the ultimate goal of being zero. For this, the time control is the critical variable on which one acts so that the extinction rate of the electric arc is as fast as possible.

Several techniques are known to meet this objective, among which it is worth noting: a) increase the separation between the fixed and mobile contacts of the electrical switch, which implies a larger volume of air between them and therefore a larger size of the switch.

- Increased speed of the firing devices.

- Radial interruption.

- Connection of simultaneous contacts in series. b) increase the length or "elongation" of the electric arc for one and the same instant in time.

- Spark extinction chambers.

- Magnetic and pneumatic blowout.

However, to implement these known devices to turn off the arcs, it is generally necessary to increase the weight and / or volume of the switches, which in turn increases the production costs, and a specific design of these switches is necessary. To achieve that purpose.

Summary of the invention

The present invention is defined in the attached independent claims and overcomes the above-mentioned prior art drawbacks, by providing a multi-pole linear switch, in which the mobile contacts thereof are advantageously configured and positioned, such as less material. of necessary for the execution of these mobile contacts, such as, in addition to the reduction of the material used, the weight of the mobile actuator is reduced, which in turn implies a faster movement of the actuator and a greater arc extinction capacity electric.

More particularly, one aspect of the invention relates to a linear multi-pole switch comprising a first group of at least two and preferably at least three fixed contacts, and a second group of at least three fixed contacts. A rectilinear displacement actuator made of an insulating material is provided in the switch to operate the same by alternately between a open position (current cut off) and a closed position (allowed current flow) of the switch.

A group of at least two and preferably at least three mobile contacts is assembled with the actuator to electrically connect in the closed position of the switch, a fixed contact of the first group and a fixed contact of the second group, and to disconnect the contacts fixed in the open position Therefore, the switch of the invention has at least three poles, in which each pole is formed by a mobile contact and its two associated fixed contacts, one of the first group and one of the second group. Each of said fixed contacts of the first and second group preferably have only one contact surface to contact their associated mobile contact.

The switch of the invention is characterized by the configuration of at least three of its mobile contacts, and by the relative arrangement between the mobile contacts and the fixed contacts. First, with respect to the configuration, each of said three mobile contacts is formed by (or consists of) a single metal plate, so that these mobile contacts can be referred to as contacts of a plate, which are preferably flat and They have upper and lower surfaces.

Therefore, in the closed position of the switch, only the upper surface or the lower surface of each of these contacts of a movable plate is contacted by a contact part of its associated fixed contacts (of the same pole) of the First and second group, while the other surface not in contact with the mobile contact of a single plate, is open which means that it is surrounded by air or in contact only with air.

Therefore, unlike prior art switches of this linear type, in which these mobile contacts have always been formed by a pair of two overlapping plates (like the one shown in Figure 1, and by the plates example (3b ', 3b ") in Figure 2C), according to the present invention, three or more of the mobile contacts are formed by a single plate.

The technical effects associated with this feature are that less is used material for the manufacture of the switch, the total weight of the actuator is reduced, and the switch capacities have been improved. An actuator weight reduction of up to 25% to 40% can be achieved with the invention, depending on the type of switch.

Some of the advantages of the invention are that manufacturing costs and production times are thereby reduced. In addition, the environmental impacts are significantly reduced due to the reduction in the use of raw materials, as well as the pollution produced during the transport of the switches.

The actuator is conventionally moved by an external drive device based on a spring or similar elastic element, in which the energy of a compressed spring is used to move the actuator when the spring is released. The reduction of actuator weight implies an additional advantage, since the actuator is now lighter, the drive device with the same energy, has to move less mass or weight, resulting in the actuator accelerating faster, and The electric arcs generated in the cutting areas are extinguished before. To this effect, they also contribute to the fact that, due to the mobile contact of a single plate, the friction between the mobile and fixed contacts is reduced, and the actuator can be accelerated even faster.

A further feature of the invention relates to the relative arrangement between these three contacts of a movable plate and the fixed contacts. According to the invention, the relative position between the mobile contact of a single plate and the fixed contacts of a pole of the switch alternate from one pole to the adjacent or consecutive ones.

The mobile contacts of a plate are positioned above or below their associated fixed contact of the same pole, and the at least three contacts of a mobile plate and the fixed contacts of the first and second group are positioned in the switch, such as the surface (upper or lower) of a single-plate mobile contact that is in contact with the associated fixed contacts, will alternate from single-plate mobile contacts to adjacent or consecutive ones. For example, if one of the poles in the mobile contact of a single plate is placed on its associated fixed contacts, at adjacent or adjacent poles formed by the mobile contacts of a single plate, the mobile contact of a single plate is placed under the respective fixed contacts

The effect associated with this characteristic is that the actuator is mechanically balanced.

Brief description of the drawings

Preferred embodiments of the invention will hereafter be described with reference to the accompanying drawings, wherein:

Figure 1 shows a linear switch of the prior art, in which the drawing (A) is a top plan view, and the drawing (B) is a perspective view.

Figure 2 shows a side view of a schematic representation of a prior art linear switch with double mobile contact plate, in which only the fixed and mobile contacts are represented for the sake of clarity of the illustration, in which the drawing (a) shows the switch in its contact or closed position, and drawing (b) shows the switch in its cut or open position. Drawing (c) is a cross-sectional view taken along line A-A in drawing (A).

Figure 3 shows a preferred embodiment of a linear switch according to the invention in its closed position, in which the drawing (a) is a side elevational view of the actuator; and the drawings (b, c) are perspective views.

Figure 4 shows a representation similar to Figure 2, but corresponding to a preferred embodiment of a linear switch according to the present invention.

Figure 5 shows the same embodiment of Figure 4 in the open position, in which the drawing (A) is a top plan view and drawing (b) is a perspective view. Figure 6 shows a representation similar to Figure 3 but corresponding to another preferred embodiment of the invention.

Figure 7 shows the same embodiment of Figure 6, but in its open position, in which the drawing (A) is a top plan view and the drawing (B) is a perspective view.

Figure 8 shows another preferred embodiment of the invention in perspective view.

Preferred Embodiment of the Invention

Figures 3 and 5 show a preferred embodiment of a multi-pole switch (6) according to the invention, in this case a four-pole switch, comprising an actuator (5) made of an insulating material, adapted and arranged in the switch to move in a straight way along the axis (X) and alternatively between an open position (figure 5) and a closed position (figure 3) of the switch.

The actuator (5) has a generally rectangular prismatic configuration having four lateral faces, two lateral sides (5a, 5b) and the upper and lower sides (5c, 5d). A group of three mobile contacts of a plate (2b, 3b, 4b) are assembled with the actuator (5) and are arranged longitudinally therein, in which each of these mobile contacts of a plate (2b, 3b, 4b ) consist of a substantially flat metal plate that has upper and lower surfaces. The two ends of these mobile contacts of a plate (2b, 3b, 4b) protrude respectively through the lateral sides (5a, 5b) of the actuator (5).

The switch (6) further comprises a first group of fixed contacts (2a, 3a, 4a) disposed on a side side (5b) of the actuator, and a second group of fixed contacts (2c, 3c, 4c) arranged on the opposite side side (5a), just as the actuator (5) is placed between the first and the second group of fixed contacts. The fixed contacts are mounted in a fixed position of a switch housing (7) (shown in Figure 5). The contacts of a mobile plate and the fixed contacts are arranged in the switch, such that each mobile contact of a single plate is electrically connected in the closed position of the switch, a fixed contact of the first group and a fixed contact of the second group . Therefore, each pole of the switch consists of a mobile contact and its associated fixed contacts, for example a first pole is defined by the contacts (1a, 1 b, 1c), a second pole is defined by the contacts (2a, 2b, 2c), a third pole is defined by the contacts (3a, 3b, 3c) and so on.

As the fixed contacts of the first and second groups have only one contact surface to contact their associated mobile contact, in the closed position of the switch, only the top or bottom surface of each of the contacts of a mobile plate , is contacted by its associated fixed contacts of the first and second group. This feature is illustrated more clearly in Figure 4, for example in the case of Figure 4C, only a part of the lower surface of the single plate movable contact (3b) is in contact with the fixed contacts (3a, 3c) of the same pole, while the upper surface thereof does not come into contact, therefore, it could be said that that part of the upper surface is completely open to air.

The same arrangement is repeated for the other poles, but with the particularity that the surface (upper or lower) of a single-plate mobile contact that is in contact with its associated fixed contacts (of the same pole), alternates with one pole to the adjacent ones.

Therefore, the relative position between the mobile contact of a single plate and the fixed contacts of a pole of the switch varies from one pole to the adjacent or consecutive ones. For example, if one of the poles in the mobile contact of a single plate is placed on its associated fixed contacts, in the adjacent or adjacent poles formed by the mobile contacts of a single plate, the mobile contact of a single plate is placed below of the respective fixed contacts.

It should be noted here that the switch (6) of the invention may also have one or more contacts of conventional double mobile plates, arranged in any position of the actuator (5). This is the case of the embodiment of Figures 3 and 5, in which the movable contact (1 b) is formed by two overlapping plates (1 b ', 1 b "). The alternate arrangement described above according to the invention, is refers only to the poles with single-plate mobile contacts.

In the embodiment of Figures 3 and 5, at the intermediate pole formed by the contacts (3a, 3b, 3c) the mobile contact (3b) is arranged below the fixed contacts (3a, 3c), while at the adjacent poles to this, that is, the poles (2a, 2b, 2c) and (4a, 4b, 4c), the respective mobile contact (2b, 4b) is placed on the respective fixed contacts (2a, 2c) and (4a, 4c ). It would be clear that in other embodiments of the invention, other configurations are possible, as long as the relative position between the movable and fixed contacts alternate from pole to any adjacent pole with a single plate movable contact. For example, in the case of Figure 4 the mobile contact (3b) of the intermediate pole is above the adjacent mobile contacts

(2b, 4b). In the embodiment of Figures 6 and 7, the four poles of the switch have movable contacts of a plate with the alternate arrangement of the contacts.

Each of the fixed contacts of the first and second groups have a substantially flat contact portion in the form of a plate, such that a contact surface is defined therein to come into contact with the associated mobile contact of a single plate. Preferably, these contact portions are substantially coplanar, that is, they are all in the same foreground (P1) (see Figure 3A). Some contacts of a mobile plate (2b, 4b) are also coplanar and are in the background (P2) above the foreground (P1), and some other contacts of a mobile plate (1 b ", 3b) are also coplanar and are in a third plane (P3) below said first plane (P1) The separation space between said second and third planes (P2, P3) is substantially similar to the thickness of the contact portion of the fixed contacts, ( see figure 4A).

It can be seen, therefore, that the alternate arrangement of contacts in these embodiments has been achieved by placing the fixed contacts in the same plane, and alternating the position of the contacts of a movable plate, up and down to form a kind of undulating arrangement that can be observed in Figures 3A, 4A, 6A. However, in other embodiments, the same effect can be achieved for example by placing the contacts of a movable plate in the same plane, and alternating up and down the position of the fixed contacts. Some poles of the switch can be connected in series, and for this the switch can include one or more metal bridges (8, 8 '), formed as a single piece (unitary body) "U" in the form of a bridge, so that Each of the two arms forms a fixed contact. In the embodiments of Figures 3, 5, 6 and 7, a first U-shaped bridge (8) has arms that define fixed contacts (3a, 4a), and a second U-shaped bridge (8 ') has arms defining fixed contacts (2c, 43), such that three poles of the switch with a single mobile contact plate are connected to each other in series through a U-shaped bridge, and a fourth pole (1 a, 2a, 3a ) is not connected to the others. In addition, the switch includes an elastic element (2e, 3e, 4e) for each single-plate mobile contact, in which the elastic elements are mounted with the actuator and together with their respective single-plate mobile contact, and are arranged to push the mobile contact of a single plate towards the associated fixed contacts in the closed position of the switch, in order to improve and maintain proper contact between the two elements. In the embodiment of Figure 3, the mobile contact of two conventional plates (1 b ', 1 b ") has a respective elastic element (1e \ 1 e").

Figure 8 shows another preferred embodiment of the invention, in which the poles (2a, 2b, 2c), (3a, 3b, 3c), (4a, 4b, 4c) are interconnected in series, and in turn are connected to this group of poles in parallel with the fourth pole or additional pole (1 a, 1 b, 1 c). This can be done, for example by connecting in the embodiment of Figure 5 or 7, a fixed contact (4c) with the fixed contact (1c) by means of a connection (9), and by the fixed contact connection (2a ) with the fixed contact (1 a) of the pole (1a, 1 b, 1 c) by means of a second connection (9 ').

These connections (9, 9 ') can be implemented in different ways, for example simply by means of a wire or plate of suitable size like the one shown in Figure 8 connecting the fixed contact. In one embodiment preferred, each of these connections (9, 9 ') consists of a single metal part element (not shown), configured to have a first part to serve as a fixed contact (e.g., the fixed contact (4c)) , a second part configured to serve as another fixed contact (for example, the fixed contact (1c)) of the same group, and a third part that connects the first and second parts.

In addition, the switch is configured so that the path that the mobile contact of the interconnected poles in series (2a, 2b, 2c), (3a, 3b, 3c), (4a, 4b, 4c) must take until contacting your respective fixed contacts is shorter than the path that the mobile contacts of the pole (1 a, 1 b, 1c), must make until contacting their respective fixed contacts, so that in the closing operation of the electric switch, the poles ( 2a, 2b, 2c), (3a, 3b, 3c), (4a, 4b, 4c) close before the fourth pole (1 a, 1 b, 1 c).

With this arrangement, in a closing operation, the interconnected poles in series (2a, 2b, 2c), (3a, 3b, 3c), (4a, 4b, 4c) are connected in the transient state, which is advantageous for interrupting the electric arc dividing it into several breakpoints, as explained above. The fourth pole (1 a, 1 b, 1 c) of less electrical resistance than in the group of interconnected poles in series, is connected in the period of permanent or rest of the switch, making a short circuit in the first mechanism, of such such that all or almost all of the current passes through this second circuit breaker mechanism during the permanent state of the switch.

Claims

1. - Multi-pole linear switch comprising:

a first group of at least two fixed contacts,

a second group of at least two fixed contacts,

a rectilinear displacement actuator made of an insulating material, which is alternately movable between an open position and a closed position of the switch,

a group of at least two mobile contacts assembled with the actuator to electrically connect in the closed position of the switch, a fixed contact of the first group and a fixed contact of the second group, such that a pole of the switch is formed by a mobile contact and its associated fixed contacts,

wherein each of said fixed contacts of the first and second group has a contact surface for contacting its associated mobile contact, characterized in that each of said two mobile contacts is a single-plate contact formed by a plate of metal having upper and lower surfaces, such as in the closed position of the switch, placing only the upper part or the lower surface of each of the mobile contacts of a single plate, in contact with their associated fixed contacts of the first and second group , and wherein said at least two mobile contacts of a single plate, and the at least two fixed contacts of the first and second group, are arranged such as the surface of a mobile contact of a single plate that is in contact with its contacts associated fixed alternating of a mobile contact of a plate to the adjacent ones.

2. - Switch according to claim 1, wherein the first group of fixed contacts comprises at least three fixed contacts, and the second group of fixed contacts comprises at least three fixed contacts, and the group of mobile contacts comprises at least Three mobile contacts.

3. - Switch according to claim 1 or 2, wherein the contacts of a mobile plate are located above or below its associated fixed contact of the same pole, and in which the contacts of a mobile plate and the Fixed contacts of the first and second group are placed on the switch, so that the position relative between the mobile contact of a single plate and the fixed contacts of one pole of the switch, alternates from one pole to the two adjacent ones.

4. - Switch according to any one of claims 1 to 3, wherein each of the fixed contacts of the first and second groups are configured to have a substantially flat contact portion (in the form of a plate) in which said contact surface is defined, and in which these contact portions are substantially coplanar.

5. - Switch according to claim 4, wherein the separation space between said second and third planes is substantially similar to the thickness of the contact portion of the fixed contacts.

6. - Switch according to any of the preceding claims, wherein the first group of fixed contacts is arranged on a first side of the actuator, and the second group of fixed contacts is arranged on a second side of the actuator, opposite the first side.

7. - Switch according to any of the preceding claims, further comprising at least one bridge obtained as a one-piece body, in which at least two fixed contacts of the same group, are parts of the bridge so that at least Two poles of the switch are interconnected in series.

8. - Switch according to claim 7, wherein the bridge is U-shaped.

9. - Switch according to any of the preceding claims, comprising at least four poles with single-plate movable contacts.

10. - Switch according to any of the preceding claims, further comprising an elastic element for each mobile contact of a single plate, in which the elastic elements are mounted with the actuator and together with their respective mobile contact of a single plate , and are arranged to push the mobile contact of a single plate towards the associated fixed contacts in the position Switch closed.

1 1. - Switch according to any of the preceding claims, comprising two or more interconnected poles in series, and wherein this group of poles is connected in parallel with an additional pole.

12. - Switch according to claim 11, wherein the switch is configured such that the path is the mobile contact of the interconnected poles in series (2a, 2b, 2c), (3a, 3b, 3c), (4a, 4b , 4c) must perform until contacting their respective fixed contacts is shorter than the path that the mobile contacts of the additional pole (1 a, 1 b, 1 c) must travel until contacting their respective fixed contacts, so that in the Electric switch closure operation, the series interconnected poles are closed before the additional pole.