WO2007093967A1

WO2007093967A1 - Safety electrical connector

Info

Publication number: WO2007093967A1
Application number: PCT/IB2007/050497
Authority: WO
Inventors: Eduardo Guillermo Harsanyi
Original assignee: Eduardo Guillermo Harsanyi; Lima Santos Luis Carlos
Priority date: 2006-02-15
Filing date: 2007-02-15
Publication date: 2007-08-23
Also published as: AR052376A1

Abstract

An electrical connector comprising: female receiving elements (2), electricity supply connectors (4), a safety device comprising a movable piston (7) made of a electricity non conducting material having upper cross arms which ends are configured as convex surfaces (10) located transversally and in contact with the female receiving elements (2), lower cross arms adapted to receive the contact terminals (6), and a resilient element (9), flexible means (5) that electrically connect the contact terminals (6) to the respective electricity supply connectors (4), wherein, the pins of the male plug, while in the inactive state, the piston (7) stays by the action of a resilient element (9) in a position that the female receiving elements (2) and the contact terminals (6) do not establish electrical contact preventing the transmission of electricity.

Description

SAFETY ELECTRICAL CONNECTOR

Field of the invention

[1] The present invention relates to electrical connectors with safety features, more particularly to electrical connectors wherein the electrical supply is interrupted when the corresponding male plug is displaced from its contact position.

Previous art

[2] In electrical installations of all kinds, and more particularly in commercial and household installations, the most common electrical connectors are those comprised by the combination of electrical outlets and plugs. Generally, outlets are fixed on the walls and permanently connected to the electricity supply line, being also in single or multiple outlet extenders allowing a proper electrical connection when the male plug pins are inserted into the openings of the outlet.

[3] Though the above mentioned electrical connectors are satisfactory from the operative point of view as they allow a quick and easy connection to the electricity supply line, safety risks they represent are known. This is because at the outlets, the electrical supply is permanent, whether the corresponding male plug is in the contact position or not. Consequently, there exists a high risk of accidents by electrocution when a metal piece is inadvertently introduced into the openings of the outlet and contacts a person. This hazard is particularly high when installations can be accessed by kids, for example most of the household installations. During games and experimentation, kids happen to introduce objects as wires, screwdrivers, or other metallic elements into outlets, producing accidents by electrocution many times fatal. The numerous cases of electrocution produced by this kind of situation have caused the development of different models of safety devices, some of them known for decades.

[4] The most known safety device is comprised of flat covers of insulating material, having projections of insulating material; also said projections are inserted tightly into the openings of outlets forming a removable cover that obstructs the respective openings preventing access to the same.

[5] This type of solution has proven insufficient to avoid electrocution accident hazards, as said covers are easily removable even by kids, which turn them little effective. Additionally, these covers must be removed when it is desired to connect a device and fitted again when removing the male plug of the respective openings of the outlet, thus most of the times, after a period of time, they are no longer used.

[6] Another type of safety device are insertable safety discs, which are installed in the outlet permanently and only allow access to the openings thereof by changing the position of a covering disc exerting a force opposing the force exerted by an elastic means, such as a spring that keeps the disc in its closed position. This type of device has the drawback that the wear produced by the use hinders fitting the plug, and so finally they are removed from the outlet.

[7] A conceptually different solution to the previous ones is represented by those electrical connectors which conductors are only connected to the electricity line when the outlet is correctly inserted in an electrical contact position. A variety of devices belong to this class of electrical connectors, which have in common the use of materials with magnetic properties.

[8] An example of this type of electrical connectors is that disclosed in US 4.242.657, dated December 30, 1980, that describes an electrical connector including a female outlet having at least one opening and a male plug to couple operatively to the female outlet. In this device, the outlet has a movable element that displaces between two positions ('disconnected' and 'connected'). A permanent magnet installed in the male plug attracts the movable element when the same is inserted into outlet openings in an electrical contact position, making said movable element to stay in the 'connected' position and allowing the flux of electricity reach the conducting members.

[9] When the male plug is removed, the movable element goes back to 'disconnected' by other magnet present inside the outlet. The response of the movable element to both magnets is obtained by the presence in the same of a magnetic element. Said magnetic element must be of 'non-permanent' type to prevent its magnetization by the extended influence of the magnets, avoiding thus the movable element moves to 'connected' in proximity of any metallic element.

[10] US 4.317.969, dated March 1, 1982, describes an electrical connector having as a technical feature the presence of two magnets. A compression spring is used to support the distributing element at an inactive state. A permanent magnet fixed to the collector port attracts a supporting magnet which makes the distributor go to its active state. A contact plate is located between the two magnets. This device is expensive to manufacture and can not be used instead of standard outlets and plugs.

[11] Other example similar to the previous examples is the device disclosed by the applicant in US 6.183.264, wherein the movable element is kept 'disconnected' by a compression spring located inside the outlet that replaces the magnetic element.

[12] A number of drawbacks make that this kind of electrical connectors of the previous art an unsatisfactory solution, mainly, because in order that said electrical connectors achieve their object they should always be used in combination with male plugs also provided with a magnetic element that cooperates with the magnetic element housed inside the outlet. This would imply that all household electrical appliances are provided with said plugs (which does not happens in the practice), or otherwise, to replace in every purchased appliance the existing plugs by plugs provided with magnets, which is an expensive and impractical alternative to the user. Moreover, said devices of the previous art are not replaceable by standard size outlets and plugs existing in the market. [13] Consequently, there exists the need to provide electrical connectors economical and easy to manufacture that do not require electrical plugs specially adapted to this end, wherein the electricity supply to the conductor elements is interrupted when the male plug is no inserted in its electrical contact position providing electricity to their elements only when electrical contact with the plug is established.

Brief description of the invention

[14] It is an object of the invention to provide an improved safety electrical connector easy to manufacture that prevents that an adult or a child receives an electrical discharge due to the inadvertent introduction of metallic objects into the openings thereof.

[15] It is another object of the invention to provide an electrical connector easy to install in electrical installations of all kinds, especially household installations, which does not require specially designed plugs, wherein the electricity supply to the conductive elements is interrupted when the male plug is offset from its electrical contact position.

[16] It is a further object of the invention to provide an outlet wherein a visual indicator allows monitoring the correct operation thereof.

[17] These objects are achieved by the present invention by an improved safety electrical connector to be used in combination with two pin conventional plugs comprising:

[18] a) an outlet and a cover;

[19] b) at least two female receiving elements adapted to receive the respective pins of the male plug;

[20] c) electricity supply connectors;

[21] d) a safety device that comprises a movable piston made of a non electricity conducting material located substantially transversally to the incoming direction of the male plug pins, wherein said piston has two ends: a lower and an upper end separated by a central stem, at the lower end two arms made of a non electricity conducting material are located, each of said arms is provided in its end with a coupling means for negative and positive contact terminals, while in its upper end said piston has two arms of non electricity conducting material, each arm has in its respective end a convex surface located within the female receptors of the pins of the male plug, and a resilient member such as a compression spring located in the piston stem, and

[22] e) flexible means connecting electrically the contact terminals to the respective electricity supply connectors.

[23] The electrical connector of the present invention operates as follows: when the male plug is not located in its electrical contact position inside the openings of the electrical connector of the present invention, the resilient means, for example a compression spring, keeps the movable piston in a position wherein the positive and negative contact terminals are separated from the corresponding female terminals. On the other hand, when the pins of a male plug come into electrical contact when inserted into the respective openings of the electrical connector, said pins push the convex side of the respective arms of the upper end of the movable piston located at the female receiving elements displacing the piston and compressing the resilient means until the positive and negative contact terminals are electrically connected to the respective female terminals closing the circuit and allowing the flux of electrical energy to the pins of the male plug.

[24] According to another embodiment, the movable piston may be located within a tubular coaxial element, wherein it displaces. Preferably, said tubular element has two slots through which the respective arm pairs located at the upper and lower ends of the movable piston, respectively, project outwardly.

[25] According to another embodiment of the invention, the flexible means connecting electrically the positive and negative female receiving elements to the electricity supply connectors are made of electricity conductive elements selected from the group consisting of cables, wires, sheets or similar conducting materials. Preferable, the conducting means are sheets of electricity conducting material fixedly coupled to the electricity supply connectors. When the flexible means is a sheet, the contact terminals are formed integrally at the flexible sheet end, fixing to the end of the cross lower arms of the movable piston. Preferably, said flexible conducting means are formed as metal sheets folded in the form of irregular polygons.

[26] In a preferred embodiment of the invention, at least one sector of the sheets of conducting material is 'V folded, having a vertex directed outwardly and the branches inwardly in relation with the female terminal, being the end of each of said branched fixed to the end of the respective lower cross arm of the movable piston.

[27] According to another preferred embodiment of the invention, at least one portion of the sheets of flexible material is 'U' folded, with the sine outwardly directed and the branches inwardly in relation with the female terminal, being the end of one of said branches fixed to the end of the respective lower cross arm of the movable piston.

[28] According to another preferred embodiment of the invention, the resilient means is located inside a tubular element where the piston displaces. Preferably, said resilient element is a compression spring partially surrounding the piston, resting by its lower end on the lower cross arms of the piston. [29] According to another preferred embodiment of the invention, the convex sides of the upper arms located at the supper end of the piston extending within the female receiving elements adapted to receive the pins of the male plug, at least are partially covered by a metallic material in order to avoid wearing of the non-conducting material when couples to the pins of the male plug during electrical contact with the same. [30] Finally, according to another preferred embodiment, the electrical connector of the present invention comprises a visual indicator, preferably a light indicator, operatively connected to the female positive and negative terminals, so that when the electrical connector is active the visual indicator turns in, while when the connector is inactive, the visual indicator goes off.

[31] Preferably, the visual indicator, housed inside the housing of the electrical connector of the present invention, is covered by a portion of the cover of said electrical connector thinner than the rest of the cover, son that it is possible to view the same with naked eye. Preferably, the indicator is a light indicator and more preferably the light indicator is a neon lamp.

Brief description of the drawings

[32] Figure 1 shows an upper perspective view showing the electrical connector of the present invention according to one embodiment of the same, said figure shows the elements of the inner portion of the electrical connector of the present invention viewed by transparency:

[33] Figure 2 A shows an upper plan view of the electrical connector of Figure 1 ;

[34] Figure 2 B shows a front view without the cover of the same;

[35] Figure 2 C shows a lateral view of the same;

[36] Figure 3 shows a perspective view of the electrical connector according to a preferred embodiment. In said figure the front cover has been removed to allow viewing the inner portion of the electrical connector; [37] Figure 4 shows the electrical connector of Figure 3 in its activated state with the male plug in its electrical connection position (only pins of the same are shown); [38] Figure 5 shows an upper perspective view of the inner elements of the electrical connector according to Figure 3, removed from the housing thereof; [39] Figure 6 A shows the movable piston of the electrical connector of Figure 3;

[40] Figure 6 B shows a flexible sheet of the electrical connector of Figure 3;

[41] Figure 6 C shows a female terminal that can be positive or negative;

[42] Figure 6 D shows the female ground terminal of Figure 3;

[43] Figure 7 shows an upper perspective view of the connector showing the aligned electricity supply connectors. [44] In all the figures, similar elements are denoted by the same references.

[45] For a better understanding of the invention, there follows a detailed description of the electrical connector of the present invention with reference to the figures, though the invention is not limited to what is shown therein.

Detailed description of the preferred embodiment of the invention

[46] According to the preferred embodiment of Figures 1 and 2, the electrical connector

(1) comprises positive and negative female receiving elements (2) and one ground receiving element (3) to establish electrical contact with the pins of the male plug when these are inserted into the openings of the electrical connector.

[47] In spite of the example shows an electrical connector adapted to three flat pin plugs, electrical connectors for plugs of three or two pins suitable for electrical installations of any voltage, either for CA or DC, are within the scope of the present invention.

[48] When the electrical connector is installed, the electricity gets to the electricity supply connectors (4) and is conducted by the flexible means (5) that connect electrically said electricity supply connectors (4) to the respective contact terminals (6).

[49] In the example of Figures 1 and 2, the flexible means (5) are electrical cables.

When electrical connector is inactive, that is when the pins of a male plug are not electrically connected to the it, the movable piston (7) to which the positive and negative contact terminals (6) are fixed at the end of the cross arms (8) is maintained by the spring (9) in a position that the contact terminals (6) are separated from the positive and negative female receiving elements (2). When the pins of a male plug are inserted into the openings of the electrical connector and displace to the electrical connection position they meet in their path the convex face (10) of the arms (26) of the upper end of the movable piston (7). Said convex surfaces of said arms (10) are located inside the positive and negative female receiving elements (2) at the end portion of the same, facing the incoming path of the respective pins of the male plug, which generates an ascending displacement force on the arms (10) causing the movable piston (7) to move vertically in the upward direction until the positive and negative contact terminals (6) establish and electrical connection with the respective positive and negative female receiving elements (2).

[50] In this way, the electricity is conducted from the electricity supply connectors (4) through the flexible means (5) and the contact terminals (6) to the positive and negative female receiving elements (2).

[51] In the examples of Figure 1 and 2, the movable piston (7) displaces inside a tubular element, wherein there is a resilient means also, such as for example a compression spring (9). Said tubular element (11) has two slots (12) through which the cross arms (8) extend outwardly and move.

[52] In this example of embodiment, the vertical movement of the movable piston (7) is limited on one hand by the stop provided by the end of the slots (12) to the movement of the cross arms (8) in the active position, and on the other by a socket (25) located at each side of the ground female receiving element (3), on which the cross arms (8) in the inactive position rest. Passing of the cross arms (8) through the slots (12) prevents rotation of the movable piston (7) over its own axis. When the pins of the male plug move away from their contact position, the resilient means (9) make the movable piston (7) to displace to its inactive or disconnected position, wherein the contact terminals (6) are separated from the positive and negative female receiving elements (2). In this way, the positive and negative female receiving elements (2) do not receive electricity, and so the introduction of any metallic element by a person that makes contact with the same does not imply any health hazard.

[53] In a preferred embodiment of the invention, the electrical connector of the present invention incorporates a light indicator such as a neon lamp (13) connected to the positive and negative female receiving elements (2). Said light indicator (13) is used to indicate that the electrical connector is active. Preferably, the light connector (13) is located in a position that it is not visible to a user when a male plug is coupled to the electrical connector.

[54] In this way, in spite of every time a device is plugged in the light turns, the user can not see it. The function of this light is apparent when the same is on after the male plug is removed, indicating thus a defective operation of the electrical connector (for example, blocking of the movable piston in its active position). Under such circumstances, said light indicator attracts immediately the attention of the user as it is a signal not perceived before. To make this mechanism more effective, the light indicator (13) may be covered by the plug cover, such that a reduced thickness portion on said cover allows viewing by transparency the light emitted by the light indicator when it is on, preventing to view the same when the indicator is off.

[55] Figures 3 to 6 show another preferred embodiment of the present invention, according to which the flexible means (5) connecting electrically the positive and negative contact terminals (6) to the electricity supply connectors (4) are sheets of electricity conducting material (for example, metal sheets) fixedly joined to the electricity supply connectors (4) and located on both sides of the ground female receiving element (3), being the positive and negative contact terminals (6) defined by an area of said sheets fixed to the end of the lower cross arms (8) of the movable piston (7). This allows simplifying the construction of the electrical connector of the present invention, eliminating steps of the manufacturing process and reducing the number of parts used, which also reduces cost. [56] In the embodiment shown in Figures 3 to 6, an area of the flexible material sheets

(5) is 'U' shaped, with the sine (14) directed outwardly and the branches (15) inwardly in relation with the ground female receiving element, being the end of one of said branches fixed to the end of the respective cross arm of the movable piston. This particular configuration of the flexible sheets (5) allows that the movement of the piston is produced as the sine of the 'U' formed by the flexible sheets (5) opens and closes. This angle variation can be seen by comparing Figure 3 to Figure 4.

[57] In Figure 3, the electrical connector is inactive and the branches (15) of the 'U' shaped flexible means formed with the flexible sheets (5) of conducting material are parallel.

[58] In Figure 4, the electrical connector in its active position is shown, that is, with the pins of the male plug (16) in a position of electrical contact, inserted into the openings of the electrical connector cover, in such a case the branches of the 'U' shaped flexible means are divergent.

[59] This angle variation of the flexible element may be produced by other configurations of the flexible sheet (for example, 'V shaped), that also fall within the scope of the present invention.

[60] The 'U' shape is advantageous in that generates less fatigue of material and therefore enables to obtain a part of longer duration. In this example of embodiment, it can be seen that the resilient means such as a compression spring (9) surrounds the movable piston (7) and rests on the cross arms (8). In this way it is possible to use resilient means longer than if they locate only above the movable piston (7), thus incrementing the force exerted by the resilient means (9) improving its function. Another particularity of this example is that the convex side (10) of the ends of the upper arms (26) of the movable piston (7) located at the positive and negative female receiving elements are coated with a metallic material to reduce wearing produced by the pins of the male plug, incrementing durability of the same.

[61] In Figure 5 it can be viewed the components of the electrical connector according to a preferred embodiment of the invention shown in Figures 3 and 4. In said Figures 3 and 4, an end perspective view is shown where the positive and negative female receiving elements (2), the ground element (3), the flexible means (5) of polygonal configuration with a 'U' shaped intermediate portion with a sine (14) and two branches (15) are viewed.

[62] According to this preferred embodiment, the positive and negative female receiving (2) and ground elements (3), the flexible means (5) and the contact terminals

(6) are made of folded metallic sheets.

[63] Figure 6 shows the different components of the electrical connector of the present invention according to the preferred embodiment shown in Figures 3 and 4.

[64] Figure 6 A shows in a perspective view a particular configuration of the movable piston (7), which has on its upper end two cross arms (26) extending transversally outwardly and at both ends of said cross arms (26) convex sides (10). On its lower end, the piston (7) has two cross arms (8) extending transversally outwardly which ends have a projection in order to fix the contact terminals (6).

[65] The movable piston (7) must be made of a non conducting material to prevent a short between the positive and negative contact terminals (6) at the ends (17) of the cross arms (8).

[66] The flexible means (5) can be formed into a flexible sheet (5) as shown in Figure 6

B. Said flexible means have an end (18) to be fixed to the respective electricity supply connector (4), an intermediate 'U' shaped portion with a sine (14) and two branches (15), an opening (19) to fix to the respective lower cross arm (8) of the movable piston (7) and a portion adjacent to said intermediate portion defining the contact terminal (6).

[67] The female receiving elements (2) shown in Figure 6C are formed by receiving means defining a space (21), such as for example two facing plates, to receive and house the pins of a male plug, and a contact portion (22) to establish an electric connection with the contact terminal (6) when the electrical connector (1) is active. Said receiving means have a wing extension with an opening (20) to connect the visual indicator (13), that preferably may be a neon lamp. Additionally, the receiving means have a recessed edge portion (27) defining a slot to receive the convex surfaces (10) of cross arms (26) of the upper end of the movable piston (7).

[68] The ground female terminal (3), adapted to receive the respective ground pin of the male plug, has a polygonal configuration and comprises a portion (24) to receive the respective ground pin of the male plug and on its line connecting end, an opening (23) for connection to the line. The particular arrangement of the components of the electrical connector of this invention allows the electricity supply connectors (4) to be located under alignment at the base of the housing of the electrical connector (1), (Figure 7), such that when there is more than one connector in the same electricity box, there is enough room between the electricity supply connectors (4) to connect easily the line cables to their respective connectors.

[69] It has to be noted that the embodiments described and illustrated are only particular examples of embodiments that the scope of the invention is not limited to, and that those modifications that may be apparent to those skilled in the art fall within the general concept of this invention.

Claims

[1] L A safety electrical connector (1) adapted to be used in combination with two or three pin male plugs, characterized in that comprises: female receiving elements (2) to receive and house the pins of a male plug, electricity supply connectors (4), a safety device operatively arranged to connect alternatively the receiving elements (2) and the contact terminal (6) between an active position and an inactive position, said safety device comprises a movable piston (7) made of a electricity non conducting material having upper cross arms which ends are configured as convex surfaces (10) located transversally and in contact with the female receiving elements (2), lower cross arms adapted to receive the contact terminals (6), and a resilient element (9), flexible means (5) that electrically connect the contact terminals (6) to the respective electricity supply connectors (4), wherein, when the electrical connector is in the active position, the movable piston (7) is moved by the action of the pins of the male plug to a position where the female receiving elements (2) and the positive and negative contact terminals (6) come into electrical contact allowing the transmission of electrical current to the pins of the male plug, while in the inactive state, the piston (7) stays by the action of a resilient element (9) in a position that the female receiving elements (2) and the contact terminals (6) do not establish electrical contact preventing the transmission of electricity.

2. An electrical connector according to claim 1, characterized in that the movable piston (7) is housed within a tubular element coaxial with said movable piston.

3. An electrical connector according to claim 2, characterized in that said tubular element that houses the movable piston (7) has two slots through which the upper and lower cross arms of the movable piston (7) pass and limit the vertical displacement of the movable piston (7) within the tubular element and rotation of the same over its own axis.

4. An electrical connector according claims 1 to 3 characterized in that the flexible means (5) are selected from electrical cables, wires or sheets.

5. An electrical connector according to claims 1 to 4, characterized in that the flexible means (5) are sheets of electricity conducting material fixedly coupled to the electricity supply connectors (4) and located on both sides of the ground female receiving element (3), being the positive and negative contact terminals (6) defined by an area of said sheets fixed to the end of the lower cross arms (8) of the movable piston (7).

6. An electrical connector according to claim 1, 4 or 5, characterized in that the flexible means (5) are metal sheets configured as irregular polygons.

7. An electrical connector according to claim 6, characterized in that at least one portion of the sheets of conducting material (5) is 'V shaped, having a sine directed outwardly and the branches inwardly in relation with the ground female terminal (3), being the end of each of said branched fixed to the end of the respective lower cross arm (8) of the movable piston (7).

8. An electrical connector according to claim 6, characterized in that at least one portion of the sheets of conducting material (5) is 'U' shaped, having the sine directed outwardly and the branches inwardly in relation with the ground female terminal, being the end of each of said branched fixed to the end of the respective lower cross arm (8) of the movable piston (7).

9. An electrical connector according to one of the claims 1 to 8, characterized in that the resilient means (9) is a compression spring located coaxial with the piston and inside the tubular element where said piston (7) moves.

10. An electrical connector according to claims 1 to 9, characterized in that the resilient means (9) is a compression spring that partially surrounds the piston, resting by one of its ends on the lower cross arms (8) of the movable piston (7).

11. An electrical connector according to claims 1 to 10, characterized in that the convex surfaces (10) of the ends of the upper cross arms (26) of the movable piston (7) are made of a metallic material.

12. An electrical connector according to claims 1 to 11, characterized in that comprises a visual indicator (13) connected to the positive and negative female receiving elements (2) such that when the electrical connector (1) stays in its active position said indicator (13) goes on and when the electrical connector is in its inactive position the visual indicator goes off.

13. An electrical connector according to claim 12, characterized in that the visual indicator (13) is covered by a portion of the cover of the electrical connector (1) of reduced thickness in relation with the rest of the cover.

14. An electrical connector according to claim 12 or 13, characterized in that the visual indicator (13) is a light indicator, preferable a neon lamp.