GB2039421A

GB2039421A - Connector

Info

Publication number: GB2039421A
Application number: GB7900612A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-01-08
Filing date: 1979-01-08
Publication date: 1980-08-06
Also published as: GB2039421B

Abstract

An electrical connector intended to be coupled together with a second similar connector, comprising a body portion (1) of insulating material enclosed in a housing (not shown) and at one end formed with a number of projecting fingers (2-5) of electrically insulating material, is characterized in that all said fingers (2,3,4) except at least one (5) are provided on their side facing toward said last mentioned finger each with a contact element (12) having a contact surface (13) smaller in width than its associated finger and that the fingers provided with the contact elements (12) are so spaced from the finger (5) with no contact that the fingers of one connector mate with the intermediate spaces of a corresponding connector. <IMAGE>

Description

SPECIFICATION Connector This invention generally relates to a connecting assembly for electric use of the kind comprising two connectors capable to be coupled together and be separated without requiring the use of any tool. The invention more precisely relates to such a connector.

At known connecting assemblies comprising two connectors, one connector, more definitely that one from which effect output is to take place, i.e. the output connector, is provided with contact elements in the form of sleeves, which are protected against electric shock hazard and, therefore, can be live even when they are separated from the second connector.

Said second connector, through which effect input is to take place, i.e. the input connector, is provided with contact elements in the form of easily accessible pins mating with the contact sleeves of the output connector. The input connector, or pin connector, thus is not protected against electric shock hazard and, therefore, must not be live when it is separated from its output connector, or sleeve connector.The fact that one connector of the known connecting assemblies includes contact elements, which are not protected against electric shock hazard, implies the possibility that by mistake or intentionally a connector, which is intended to be an input connector and provided with accessible contact elements, is used as a live output connector, which when being touched can cause serious injuries, especially when it is connected to a 220V or 380V circuit of two-phase or three-phase type. This is a serious disadvantage of the conventional connectors and entirely unsatisfactory from a safety point of view.

The present invention, therefore, has the object to provide a connector, which can be used as an output connector together with a similar connector used as input connector, or as an input connector together with a similar connector used as output connector, and which is protected against electric shock hazard irrespective of its use as output or input connector in a connecting assembly comprising two such connectors, and by which such a connector is simplified and its manufacture and stock-keeping cheapened, because one and the same type of connector can be used both as input and output connector, which latter possibility does not exist with conventional connectors.

This object is achieved in that the connector according to the invention has been given the characterizing features defined in the attached claims.

The invention is described in greater detail in the following, with reference to the accompanying drawings, in which Figure 1 is a lateral view of a first embodiment of the connector according to the invention used as an output connector, Figure2 is a lateral view, partially in section, of a similar connector as that shown in Figure 1, but used as an input connector mating with the output connector in Figure 1, Figure 3 is a section along the line il-ll in Figure 1, Figure 4 is a horizontal view of only a portion of a second embodiment of the connector according to the invention, Figure 5 is a section along the line V-V in Figure 4, Figure 6 is a section along the line VI-VI in Figure 4, showing the connector used as an output connector, Figure 7 is a section of a similar connector as that shown in Figures 4-5, but used as an input connector mating with the output connector in Figure 6, and Figure 8 shows a slightly modified embodiment of the connector according to the invention shown in Figures 4-7.

In the drawings some embodiments of the connector according to the invention are illustrated only by way of example, without enclosing housing and connections, because these details per se are not required for elucidating the invention. The examples shown, furthermore, are intended for a five-wire, i.e.

a circuit with three phases, one neutral wire and non-fused earth conductor, which in known manner is connected to the housing of the connector, for example by means of a protective screw. The invention, however, is not restricted to just this type of circuit, but can be applied to all types of power systems.

The connector according to the invention comprises a body portion 1, which at the embodiment according to Figures 1 - 3 is made integer from an insulating material, as for example hard rubber, bakelite, plastic, porcelain or other material suitable, for example, for compression molding or mold casting, with fingers 2,3,4 and 5, preferably of rectangular cross-section, which project at one end of the body portion and are disposed above each other, as shown in Figure 3.Said fingers, which are spaced apart relative to each other by gaps 6,7 and, respectively, 8, have equal length, but are at said embodiment so offset relative to each other, that the finger 3 extends past the finger 2 an equal distance as the finger 4 extends past the finger 3, while the finger 5, which substantially acts as a protection, is shown having the same extension as the finger 4, counted from the bottom 9 of the gap 8.The fingers 2,3 and 4 at the embodiment according to Figures 1 3 have equal thickness corresponding to the distance between two fingers i.e. the gap height is the same for all gaps in the cases when the fingers 2,3 and 4 have the same thickness, while the finger 5 has a slightly greater thickness than the remaining fingers and preferably a thickness, which corresponds to the distance from upper surface 10 of the finger 2 shown in Figure 1 to the upper surface 11 of the body portion, and which should exceed the height of the gaps, for reasons to be explained in greater detail later on in this descriptive part.In this connection mentioning should be made, that the fingers 2,3 and 4 within the scope of the invention may be given a varying thickness, provided that the gap 8 is given a height corresponding to the thickness of the finger 2, the gap 7 is given a height corresponding to the thickness of the finger 3, and the gap 6 is given a height corresponding to the thickness of the finger 4.

In all cases, however, the gap height must not be so great that one finger of a person can enter between two fingers of the body portion. The gap height, thus, must not be greater than 4-5 mm, preferably 2-3 mm.

In that surface of each of the fingers 2, 3 and 4 which faces to the protective finger 5, contact elements 12 are sunk into grooves so that each such element, which may consist of a relatively thin metal bar with a width smaller than the width of the respective finger, shows an exposed contact surface 13, which preferably is resilient or bulging outward in the direction from the groove bottom, and which should terminate spaced from the free end 14 of the respective fingers, in order to render the access to the contact elements 12 still more difficult, which also with their longitudinal edges are located inside of the longitudinal edges of the respective fingers, as is apparent especially in Figure 3.Said grooves, into which the contact elements are sunk, of course must have such a depth adjusted to the thickness of the contact element, that the contact element never can be located with its contact surface 13 inside of a plane through and in parallel with that lateral surface of the respective fingers which faces to the finger 5.

Every contact bar 12 extends all the way to the end 15 of the body portion where the bars in some known manner, for example by contact screws, terminals, soldering or similar arrangement, can be connected to the three phases of a wire. Said end 15 may have a stepped design in order to render the connecting easier, though this design is not shown in the Figures. The neutral wire of the circuit is connected to contact elements 16 provided for this purpose on the connector, which elements at the embodiment shown in the drawings have the form of a U-shaped metal bar, the legs 17 of which extend over the greater part of the height of the body portion from the finger 5, which protects the contact elements 12 of the finger 4 against touch. In Figure 1 as well as in Figures 4 - 7, the contact element 16 for the neutral wire is indicated only by a dash-dotted contour line.By addition of a further finger and associated contact element to the connector, of course, the neutral wire of the circuit can be connected to this contact element, thereby rendering superflous the contact element 16 shown in the drawing. This applies particularly to the embodiment according to Figures 4 - 8. At the embodiment according to Figures 1 - 3, the U-shaped contact element, however, is to be preferred to an additional finger with associated contact element a.o. for mounting-technical reasons, because the contact element for the neutral wire hereby is better distinguished from the remaining contact elements intended for other wires of the circuit, and there is less risk of connecting the neutral wire wrongly.The U-shaped contact element 16 further provides a larger contact surface than a contact element of the type designated by 12, and it acts as an additional protection against touching the contact elements 12 of the fingers, because the element 16 with its legs 17 covers the gaps 6,7 and 8 between the fingers from the side. The contact elements 12 of the fingers, thus, are located well protected and difficult to get at within the body portion 1. For shielding the contact element 16 from the housing (not shown) of the connector, the housing preferably is provided on its inner surface with a layer of an insulating material, which prevnts electric contact between the contact element 16 and the housing.

In Figure 1 the connector according to the invention is shown applied as an output connector, the contact elements 12 of which are located entirely protected against touch and, therefore, may be live even when the connector is not coupled together with another connector. In Figure 2 is also shown a connector according to the invention which is iden ticallyequal with the connector shown in Figure 1, but which is applied as an input connector by having been turned through 1800 about both a horizontal and a vertical axis in relation to the connector shown in Figure 1.The contact elements 12 of the connector, even when it is used as input connector, are located entirely protected against touch and, therefore, the connector according to the invention can be used both as input and as output connector without any live contact element being accessible, not even when the connectors are completely separated from each other. The two connectors shown as output connector and input connector is Figures 1 and 2 are coupled together very simply by manually pushing the connectors together, whereby the finger 5 due to its thickness exceeding the height of each gap prevents any form of wrong connection of the connectors.When the connectors are being pushed together, thus, the contact elements 12 and the contact elements 16 in the two connectors are caused to abut each other, and when they are completely pushed together, a good electric contact between them is established. The contact pressure between the contact bars 15 can be made adjustable, when required, by means of special adjusting screws (not shown), and the contact bars further can be provided with longitudinal slots and be designed to bulge outward in different degrees in order to bring about the necessary contact pressure. In order to separate the connectors, they are very simply be pulled apart, whereby flash-over between the contact elements 12 substantially is eleminated owing to the stepped design of the fingers 2 - 4.

The housing (not shown) of the connector may be made of compression molded aluminum and should so be formed, that it does not restrict the connector according to the invention to be used either as output connector or as input connector, but permits the connector to be used for both purposes.

At the embodiment of the connector illustrated in Figures 4 - 7 the fingers 2, 3 and 4 with associated contact elements 12 terminating before the free end 14 of the fingers are arranged to the side of each other in one and the same plane and at a distance from the thicker protective finger 5 corresponding to the thickness of the fingers 2,3 and 4, which as mentioned above must not exceed 5 mm. The fingers 2,3 and 4 in Figures 4 - 7 are shown to have equal thickness, but they may be designed with different thicknesses, provided that the distance between the fingers 4 and 5 is made equal to the thickness of the finger 2, that the distance between the fingers 3 and 5 is made equal to the thickness of the finger 3, and that the distance between the fingers 2 and 5 is made equal to the thickness of the finger 4.The protective finger 5 at this embodiment has a greater length than the fingers 2,3 and 4, and it may have it also at the embodiment shown in Figures 1 and 3, and it may have a greater lateral extension than the fingers 2,3 and 4, thereby rendering the access to the contact elements 12 more difficult.At the modificaton shown in Figure 8 of the embodimentshown in Figures 4 - 7 it is entirely impossible to touch the elements 12 from the side, because the protective finger 5 on its side facing to the remaining fingers 2 - 4 is formed with ridges 20 on both sides of each finger 2, 3 and 4, which ridges have a height corresponding accurately to the thickness of the fingers 2,3 and 4 so that the free side 21 of the ridges 20 is located on exactly the same level as the side of the fingers which faces to the protective finger 5, i.e. the ridges must not be higher than half the distance between the side 22 of the protective finger 5 which faces to the contact elements 22 and the side 23 of a finger 2, 3 or 4 remote from the finger 5 (Figures 6 and 7).

A great advantage of the embodiments shown in Figures 4-8 is the achievement of phase agreement between two connectors, irrespective of the number of fingers provided with contact elements, because the fingers provided with contact elements of one connector (see Figure 6) will be located directly in front of and co-operate with corresponding fingers provided with contact elements of a second connector (see Figure 7). The finger 4, for example, at the connector shown in Figure 6 will be located above the finger 4 of the connector shown in Figure 7. At this embodiment, thus, no U-shaped contact element 17 shown in the Figures is required for the connecting of the neutral phase, but this connecting can be made directly to the contact elements of corresponding fingers of the connectors according to this embodiment of the invention.In order to facilitate the connecting of multiple conductors, the different fingers of the connectors can be coloured according to international standard.

At the embodiment according to Figures 4-8, the body portion 1 consists of two detachably connected portions 24 and 25. The parting line between these portion coincides with the side of the fingers 2,3 and 4 which in Figures 6 and 7 is designated by 26.

The present invention is not restricted to what is described above and shown in the drawings, but can be altered, mo-ified and completed in many different ways within the scope of the invention idea as it is set forth in the claims. The body portion, for example, also at the embodiment shown in Figures 1-3 may be assembled of plates of an insulating material which are detachably jointed and have a thickness corresponding to that of the fingers, and between said plates intermediate layers of insulating material may be arranged to form the gaps between the fingers. The free ends 14 of the fingers also at the embodiment shown in Figures 1-3 may be located in one and the same plane. It is also possible to design the three fingers 2,3 and 4 as a single finger, the contact elements being arranged in grooves in that side of this finger which faces to the protective finger and spaced apart from each other.

Claims

1. A connector of the kind intended to be coupled together with a second similar connector for electric connection, comprising a body portion of insulating material enclosed in a housing and at one end formed with a number of projecting fingers of electrically insulating material, characterized in that all said fingers (2,3,4,5) except at least one are provided on their side facing toward said lastmentioned finger each with a contact element (12) having a contact surface (13) smaller than the surface of said side, that intermediate spaces (6,7,8) are provided between each finger provided with said contact element (12) and the finger, to which such finger faces with its contact element, and said intermediate spaces have a height corresponding to the thickness of said fingers, so that the fingers of one connector mate with the intermediate spaces of a corresponding connector.

2. A connector as defined in claim 1, characterized in that the contact elements (12) terminate at such a distance from the free end (14) ofthe respective fingers in relation to the height of the intermediate space, that the contact elements are unaccessible for touch by persons.

3. A connector as defined in claim 1 or 2, characterized in that the fingers (2,3,4) provided with contact elements (12) are arranged to the side of each other in one and the same plane and their contact elements (12) face toward the finger or fingers (5) having no contact element, whereby phase agreement between two connectors is achieved.

4. A connector as defined in claim 1,2 or 3, characterized in that the finger or fingers (5) having no contact element have a greater extension in longitudinal direction than the fingers (2,3,4) provided with contact elements.

5. A connector as defined in any one of the preceding claims, characterized in that the finger or fingers (5) having no contact element extend in lateral direction past the two outer ones of the fingers (2,3,4) provided with contact elements,

6. A connector as defined in any one of the claims 1-4, characterized in that the finger or fingers (5) having no contact element are provided on their side facing toward the contact elements (12) with ridges (20) located on both sides of each finger (2,3,4) provided with contact elements (12).

7. A connector as defined in any one of the preceding claims, characterized in that the longitudinal edges of the contact elements are located inside of the longitudinal edges of the respective fingers.

8. A connector as defined in any one of the preceding claims, characterized in that the one of the fingers (2,3,4,5) which has no contact element (12) has a thickness exceeding the height of the greatest intermediate space.

9. A connector as defined in any one of the preceding claims, characterized in that the contact elements (12) are located sunk into the respective finger (2,3,4).

10. A connector as defined in any one of the claims 3-9, characterized in that the fingers (2,3,4,5) with their free ends are located offset relative to each other to form a stepped design, in such a manner, that the finger (5) having no contact element projects farthest out with its free end, or at least as far as the one of the fingers (2,3,4) provided with contact elements which projects out farthest, which lastmentioned finger (4) is located closest to the finger (5) having no contact element.

11. A connector substantially as hereinbefore described with reference to Figures 1 to 3, Figures 4 to 7 or Figure 8 of the accompanying drawings.

12. In combination, a connector as claimed in any one of the preceding claims and a second similar connector, for coupling together to provide electrical connection.