Contact bar having sockets and a ganged plug-in unit having such a contact bar

Abstract: This invention relates to a contact bar having plug-in sockets, with a power bar (1) from which lateral webs (15) extend comb-fashion, plug-in sockets (16) being formed on the webs. The sockets have resilient first spring arms (2) which extend upwards at an inclination to one another from a baseplate (17) which either forms or is connected to the webs (15) as far as their plug-in end where they are bent round to widen funnel-fashion in order to facilitate the introduction of a blade contact (18), each spring arm pair (2) having an overspring (3) which also has two spring arms covering a larger part of the first spring arms and starting from a unitary baseplate (19) in a corresponding number and pressing the first spring arms (2) together at their ends. The invention also relates to a ganged plug-in unit having such contact bars.

Description: This invention relates to a contact bar having plug-in sockets as set out in the preamble of claim 1. It also relates to a ganged plug-in unit which uses such a contact bar. Such contact bars and ganged plug-in units are used more particularly in the installation of networks where currents of the order of magnitude of several amperes at a voltage of several hundred volts flow. The protection features required in such installations usually consist of a number of automatic cut-outs arranged as ganged plug-in units on a panel in a switch box. If the overall depth and other dimensions of this arrangement are to be as compact as possible, the important consideration is for the spring contacts and contact blades to be very low and for them to be arranged beside one another as compactly as possible. Prior art document GB-A-2 036 437 discloses several pairs of sockets integral with a bus bar, the sockets consisting of two opposed spring arms and extending combwise from the bus bar. Prior art document FR-A-1 276 672 discloses a connector having two opposed U-shaped legs and an overspring super imposed over said legs. It is the object of the invention to provide a contact bar having spring contacts and sockets and a ganged plug-in unit having such a contact bar which is simple to manipulate and is very flat and compact. This problem is solved in accordance with claim 1. The sub-claims disclose preferred embodiments of the contact bar and ganged plug-in unit according to the invention. An embodiment of the invention will be described in greater detail hereinafter with reference to the drawings wherein: Figures 1a and 1b are each a view in section through a ganged plug-in unit, the view being taken transversely through a socket; Figure 2 is a partly sectioned view in side elevation of a web with the outer spring assembled; Figure 3 is a plan view of a contact bar with webs and sockets; Figure 4 is a plan view of a ganged plug-in unit casing with its cover removed; Figure 5 shows a cover for the unit of Figure 4; Figure 6 is a section on the line A - B of Figure 5 and a detailed view of the bevelled contact blades, and Figure 7 is a plan view of a three-pole embodiment of a ganged plug-in unit according to the invention. Figure 1a is a view in cross-section of a socket 16. Some of the cover of the plug-in unit casing is shown above the socket 16 and is formed with an entry for a contact blade. The casing cover and the casing base are slightly recessed at the places where the sockets 16 are disposed in order to facilitate adjustment of the arrangement and to reduce overall height. Socket 16 has resilient first spring arms 2 which are good electrical conductors and which extend upwards at a diagonal inclination towards one another from a baseplate 17 and extend out apart from one another funnel-fashion at the top. The introduction of a blade contact 18 is therefore facilitated. The ends of the spring arms are so pressed towards one another by second spring arms 3 forming an overspring that in the absence of blade contact the entry end of the socket 16 is kept substantially closed by the pressed-together first spring arms 2. The second spring arms 3 have a baseplate 19 and their arms extend upwards at a reduced inclination to one another. Depending upon the construction the baseplate 17 of the socket 16 serves as a web welded to a power bar 1 or the whole consists of a step-rolled part in which the bar 1 and the webs and therefore the baseplate sockets and their first spring arms are made of the same material rolled or punched in different thicknesses. Figure 1b shows a socket 16 with a blade contact 18 half-inserted. As will be apparent, in this position the overspring arms are pressed slightly apart from one another so that the spring force to be overcome consists of the spring force of the first spring arms and the spring force of the spring arms of the overspring. Figure 2 is a view of a socket in side elevation. In this embodiment the webs are connected unitarily in comb fashion to a sheet metal member which has the dimensions of the bar 1 and which is welded thereto. The socket has three spring arm pairs over which three respective overspring arm pairs engage. The overspring 3 has a unitary baseplate 19 having at its four corners tabs 21 which extend over the baseplate 17 in order to secure the overspring to the web 15. It has been found very advantageous to provide three spring arm pairs since this number provides optimum contact with the contact blade in the event of irregularities occurring because of twisting or of being fitted in a tilted position. As can be seen in Figure 1, to give the sockets some freedom to twist around a longitudinal axis, ribs 23 enabling the webs 15 to twist or tilt around their longitudinal axes are disposed in the base of the plug-in unit casing parallel to the longitudinal axis of the webs 15. The same effect can be achieved by a reversal - i.e., a flat casing support and a spherical spring base. Figure 3 is a plan view of a contact bar which has sockets. There can be seen the power bar 1 which is connected by a number of spot welds to a comb consisting of a number of unitary webs 15. A cable connection 4 is welded to the bar 1. As is shown, for example in Figure 4, there is room for at least two such contact bars in a casing 22. The connecting cables are led out of the casing on the same side and the casing base has S-shaped partition segments which facilitate the positioning of the contact bars and provide reliable insulation between the web tips. The two contact bars shown are in this case so disposed as to engage slightly in one another. Figure 5 shows the cover associated with the casing of Figure 4. As will be apparent, six module segments each having two sockets and locating pins are shown. The slots 6a, 6b are disposed opposite the sockets 16 whereas the apertures 7 for the locating pins 9 ensure that the companion elements are accurately arranged in space. In the particular case illustrated the companion elements are electrical appliances which, as shown in Figure 6, are disposed on a fixing bar 12 and plug into the ganged plug-in units. To this end, a locating pin 11 first engages in a recess 10 in the plug-in unit casing till the electrical appliance engages the edge of the bar 12, whereafter the opposite end of the appliance is so pressed down that the contact blades engage in the sockets. Also, the locating pin 9 engages in the associated aperture 7. As Figure 6 also shows, the contact blades have a slightly curved front edge so oriented as also to make contact with the entry ends of the spring arms during the inwards pivoting movement. Figure 7 shows a three-pole construction of a plug-in unit casing according to the invention, the power bars 25, 26, 27 and the neutral bars 28 being flexibly interconnected by way of a respective stranded wire 13 and connecting wire 4. As in the example hereinbefore described the connecting wires 4 are welded to the power bars. To insulate the power bars or webs from one another, they can be coated wholly or in part on one or both sides with a plastics film. In Figure 7 the insulation is provided near the connection to the stranded wire 13 by the provision of a plastics cap 14. The description of this embodiment serves merely to explain the invention defined in the claims.

Claims: A contact bar having plug-in sockets, with a power bar (1) from which webs (15) extend laterally combwise, plug-in sockets (16) being devised on the webs (15), the sockets (16) having resilient first spring arms (2) which extend upwards, from a baseplate (17) which either forms or is connected to the webs (15), at an inclination towards one another as far as their plug-in end where they are bent round to widen funnel-fashion to facilitate the entry of a blade contact (18), characterised in that each spring arm pair (2) has an overspring (3) which also has second spring arms covering a large part of the first spring arms and starting from a unitary baseplate (18) in a corresponding number, the second spring arms pressing the first spring arms (2) together at their ends, and the overspring (3) has a baseplate (19) at whose four corners a tab (21) engages over the baseplate of the first spring arms (17) in order to secure the overspring on the latter baseplate. A contact bar according to claim 1, characterised in that each socket (16) has six first and second spring arms (2, 3). A contact bar according to claim 1 or 2, characterised in that the webs (15) are integral with the first spring arms (2) and with a bar (20) welded to the power bar (1). A contact bar according to any of claims 1 to 3, characterised in that the webs are unitarily connected in comb-fashion to a sheet of metal member, the whole consisting of a step-rolled part in which the power bar and the webs and, therefore, the baseplate sockets and their first spring arms are made of the same material rolled or punched in different thicknesses. A contact bar according to any of claims 1 to 4, characterised in that the baseplate (17) of the sockets (16) is pivotable around the longitudinal axis of the webs. A contact bar according to any of claims 1 to 5, characterised in that a pluggable or permanently welded line connection (4) is provided on the power bar (1). A ganged plug-in unit having a contact bar according to any of claims 1 to 6, characterised in that at least two contact bars are so disposed in a casing (22) that the webs (15) of different bars (1) are disposed in toothed relationship to one another, their front ends being insulated from one another by partitions (5) anchored in the casing. A ganged plug-in unit according to claim 7, characterised in that the sockets (16) are mounted on a rib (23) formed parallel to their longitudinal axis in the casing base and permitting twisting of the socket. A ganged plug-in unit according to claim 7 or 8, characterised in that slots (6a, 6b) opposite the sockets and additional apertures (7, 10) for locating pins (9, 11) are present on the top of the casing (22). A ganged plug-in unit according to claim 9, characterised in that the companion elements are automatic cut-outs and the same are secured to a fixing bar (12) on the top of the casing and are located by means of the locating pins (9). A ganged plug-in unit according to claim 10, characterised in that the automatic cut-outs can be hung by way of their sides opposite the slots (6a, 6b) on the fixing bar (12), whereafter the contact blades (8a, 8b) and the locating pin (9) can be pivoted into the slots (6a, 6b) and adjusting aperture (7) respectively, the end edges of the contact blades (8a, 8b) being bevelled so that all the contacting points on the end edge of the contact blades (8a, 8b) engage simultaneously in each socket (16). A ganged plug-in unit according to any of claims 7 to 11, characterised in that three contact bars (1) are provided for a three-pole construction, their webs (15) being so devised in part as to be able to bridge an adjacent power bar (1) without contacting it. A ganged plug-in unit according to claim 12, characterised in that the power bar and parts of the webs (15) are covered by a protective plastics cap (14) for insulation. A ganged plug-in unit according to claim 12, characterised in that the power bar and parts of the webs (15) are coated with an insulating plastics film. A ganged plug-in unit according to any of claims 7 to 11, characterised in that the power bars (25, 26, 27) and neutral bars (28) are respectively interconnected flexibly by way of a stranded wire (13) and connecting wire (4) respectively.

Inventors: RITTER FRIEDHELM, RITTER,FRIEDHELM
Applicants: FRAMATOME CONNECTORS INT, FRAMATOME CONNECTORS INTERNATIONAL
Application year: 1997
Main classification: H02B1
IPC codes: H02B1, H01R13