GB2240224A

GB2240224A - Plug-in electrical adaptor

Info

Publication number: GB2240224A
Application number: GB9027362A
Authority: GB
Inventors: Wolfgang Essrich; Bernhard Burkard
Original assignee: Souriau Electric GmbH
Current assignee: Souriau Electric GmbH
Priority date: 1989-12-20
Filing date: 1990-12-18
Publication date: 1991-07-24
Also published as: GB9027362D0; FR2656160A1

Abstract

An adaptor for the transmission of electrical measurement signals from a plug part (10), which can be plugged in on the input side, to a connector part (46), which can be connected at the output side, and which has running therein one or more contacts (26) for connecting electrically the plug part with the connector part. The contacts (26) are, at their ends (34) which face the plug part (10), movable within the housing (22, 24) of the adaptor in such a manner that when the plug part is plugged in, it touches each of the contacts at a distance from the free end (34) of the contact at a curved central portion (38) and when the plug part is pushed in further, it urges the free end (34) of the contact in a perpendicular direction against the corresponding contact of the plug part. The plug part (10) may be a card carrying a reaction surface for blood analysis, the connector (46) then being part of an analysis device. <IMAGE>

Description

Adaptor The invention concerns an adaptor for the transmission of electrical measuring signals from a plug part capable of being plugged in at the input side to a connector part capable of being connected at the output side by means of one or more contacts running through it for electrical connection of the plug part with the connector part.

Adaptors for the transmission of electrical measuring signals are required in numerous spheres of technology. In view of their function one might also refer to them as plug-connectors, wherein a single or multi-pole electrical connection emanating from an electrical supply is made across the plug-connector to connector parts at the output side.

This class of plug-connectors/adaptors also includes devices in which the parts on the connector side are not connected to the adaptor in a stationary manner, but where the connection is made by a greater or smaller number of temporary insertion cycles Such devices are for instance known from automatic telephones, where the telephone installation is activated by an insert card which is inserted and withdrawn time and again.

In order to provide a sure connection between the contacts of the plug so temporarily inserted and the contacts of the adaptor even after the 100th or 1,000th insertion cycle, the frictional forces between the contacts must not be too great, in order to prevent wear in the region of the contacts, which would necessarily lead to faults.

The object of the invention is therefore to provide an adaptor (plug-connector) which is contacted at least at one of its two ends on the connection side through a plug element, so that the contact is to be made in such a way that the frictional forces arising between the sections of contact of the plugged-in part and the contact elements of the plug-connector are as small as possible, in order to provide a sure contact even when the insertion cycles are high.

The invention is based on the recognition that this aim can be attained in a simple manner by tilting the contact.

sections of the contacts within the adaptor normally (i.e.

perpendicularly) against the corresponding contacts of the plug part, and essentially doing this only when the plug part has attained its ultimate position. It follows therefrom that in accordance with the invention the plug is first inserted to a certain distance into the plug-connector without contacting the contacts of the latter and that the contact sections of the contacts of the plug-connector (adaptor) are only tilted against the contacts of the plug part in the last moment, shortly before the plug part has attained its ultimate position in the plug-connector.

In this way sliding friction between the corresponding contacts of the adaptor and those of the plug part is avoided and hence also the risk of wear in the region of the contact surfaces. This makes it possible to provide a sure contact of the contacts even after 100 or 1,000 or more insertion cycles, without any wear taking place which would eventually lead to faults such as one pair of contacts being electrically connected with the next pair of contacts.

Such an adaptor is distinguished in its general form of design in that the contacts are arranged at their end facing the plug part in such a manner that they can move within the housing of the adaptor so that on insertion of the plug part the latter touches the contacts at a distance from the free end of the contact on the plug side and on further insertion of the plug part guides the free ends of the contacts in a normal (perpendicular) direction against the corresponding contacts of the plug part.

In an advantageous form of design the contacts have, at a distance from the free end of the contact on the plug side, a section projecting in the direction of the contacts of the plug part, which section should preferably in the un-plugged state be at a distance from the corresponding inner surface of the housing of the adaptor slightly smaller than the thickness of the plug part with its contacts.

This enables the plug part on its insertion to be at first introduced freely in the adaptor and to position it only shortly before reaching the ultimate plug position in the region of the projecting sections, whereby the projecting sections at the same time serve to tilt the free end region of the contacts of the adaptor against the contacts of the plug part by means of appropriate devices.

For this purpose it is proposed in an advantageous form of design to provide the contacts with a bearing section on the side opposite the projecting section and located between their projecting sections and their free ends.

This bearing section can either itself be a part of the contact in that, for example, these have a protrubrance pointing in the direction opposite to that of the projecting sections and which either already bears against the corresponding part of the adaptor housing or is at a slight distance from it. The adaptor contacts are only tilted about this bearing section at the latest at the moment when the plug part is inserted in the gap between the projecting sections and the corresponding part of the adaptor housing, so that the free ends of the contacts are guided against the contact sections of the plug part in a direction perpendicular to these.

In an alternative form of design the bearing point is formed by an appropriate bearing in the adaptor housing itself. This bearing dan then consist of a protruberance which protrudes into a cavity from the inner part of the housing in a direction perpendicular to the length of the contacts.

This characteristic is additionally explained by the following detailed description of an example of a design.

The free ends of the adaptor contacts are preferably bent at right angles in such a manner that the appropriate contact surfaces protrude in the direction of the contacts of the plug part. On the one hand this shortens the passage necessary to attain a contact with the contacts of the plug part and on the other hand permits the contact surface itself to be kept small. For this characteristic reference is also made to the attached pictorial description.

The contacts should of course also be positioned securely in the adaptor and for this reason it is proposed to hold the contacts firmly in place approximately in the m,iddle between the plug end and the contact end.

In an advantageóus form of design ridges made of an insulating material running longitudinally between the contacts are to be provided for the purpose of insulating the contacts from each other within the adaptor, so that each individual contact lies practically in its own bed.

For the purpose of fitting the adaptor with the corresponding contacts it is advantageous to form the housing in two parts and only to join these when the contacts have been placed therein.

In order that each contact does not have to be placed in the housing individually, especially in the case of multi-pole devices, the invention further proposes the production of the contacts in a single operation where the individual contacts are connected with each other by bridges which are then severed by approporiate tools when the housing is closed. For this purpose the housing has appropriate holes through it in the areas where there are originally the connecting points between the contacts.

These holes permit the connecting points to be subsequently severed by means of an appropriate tool so that individual contacts are electrically insulated from each other. For a further explanation reference is again made to the pictorial description.

Although the adaptor is simply designed and can be simply produced it has the essential advantage over known plugconnectors in that contact no longer takes place in a sliding manner over longer surface sections, but in a quasi stationary manner by the tilting of the adaptor contacts against the contacts of the plug part.

Further characteristic features become evident from the characteristic features of the subsidiary claims and other application documents.

The invention is hereunder further explained by means of an example of a design where the adaptor described and very schematically represented in the drawing serves to accept an insert card which has several surface contacts by which an electrical connection is to be made throught the adaptor to the output end in a connector part located there.

The individual figures showy Figure 1: A plan view of an insertion card for insertion in an adaptor Figure 2: A logitudinal cross-section through an adaptor in the state before assembly Figure 3: A longitudinal cross-section through the adaptor in accordance with Figure 2 with an insertion card inserted, but before the in-contact state Figure 4: A longitudinal cross-section through the adaptor in accordance with Figure 2 in the plugged-in state Figure 5: A plan view of the contacts before assembly For a clearer understanding the construction and the function of the insertion card shown in Figure 1 will first be explained.

The insertion card consists of a flat paper body on the forward side of which there is a chemically active reaction surface 12 from which four contact strips 14a-d which are at a distance from each other run in the direction of the length of the insert card 10 towards the lower end thereof in Figure 1 and terminate there at a distance from said lower end. The contact strips 14a-d are printed, glued or similarly attached to the insertion card 10 and are made from a low friction material such as graphite.

In this case the insert card 10 serves for blood analysis where a drop of the patient's blood is placed on the reaction surface 12 and there causes a chemical reaction which can at the same time be measured by the electrical conductivity of the contact strips 14a-d which are connected to the reaction surface 12. This requires an appropriate analysis device. The above mentioned adaptor shown in Figures 2 to 4 is required for the transmission of the electrical measuring signals from the contact strips 14a-d to the analysis device.

The adaptor 20 consists of two plastic parts 22, 24 which can for example be produced by injection moulding and of several contacts 26 made of electrically conductive material, for example bronze. The number of contacts 26 corresponds to the number of contact strips 14a-d and therefore amounts in this case to four.

As the cross-sections 2 to 4 show, the parts 22, 24 of the adaptor 20 are made with numerous protruberances and recesses which firstly serve to connect the parts 22, 24 and secondly permit the admission of the contacts 26.

Of special importance for this are firstly the recesses 28 in the region of the connector side of part 22 which are each limited by a protruberance 30 at a distance from the end on the plug side.

The configuration of the parts 22, 24 is further so chosen in relation to each other that after they are connected by means of appropriate catch devices (not shown) the contacts 26 sit firmly between the parts 22, 24, are however at the same time freely movable at least at their plug side end, as will be further explained in greater detail. As may be seen from Figure 3, the contacts 26 are situated particularly in their middle region on corresponding surfaces of the parts 22, 24 so that they cannot slip out of place. Guidance is also provided sideways by ridges (such as 32) between the contacts.

As shown in section in Figure 2, the contacts 26 have various bends and curves of which particularly the bends 34, 36 at the ends and the curve 38 in the middle are of special importance, as will further be explained in greater detail.

It is important that the curve 38 be situated in the adaptor at a distance from the corresponding surface of part 24, while at the same time the section 40 between the curve 38 and the bend 34 is situated on a protruberance 30 and the free end of the bend 34 is at a distance from the corresponding surface of the part 24, the distance of the bend 34 from the corresponding surface of the part 24 being at first (Figure 3) greater than the distance between the curve 38 from the corresponding surface of the part 24.

This positioning permits the forward end 10a of the above mentioned insert card 10 to be slid into a slot on the plug-in side of the adaptor 20 in such a manner that the contact strips 14a-d are situated opposite the corresponding contacts 26 in the adaptor 20.

As shown in Figure 3, the positioning of the contacts 26 is chosen so that the free end of the insert card 10 (this end being free of contact strips) first abuts the curve 38 and, when the insert card is pushed in further, pushes the curve 38 aside (Figure 4), whereby due to the leverage the section 40 swings about the protruberance 30 causing the bend 34 to be pressed against the insert card 10. (Figure 4).

In this position (Figure 4) the contact strips 14a-d are brought into contact with the corresponding bends 34 of the contacts 26 exclusively in a perpendicular direction so that wear is avoided particularly in the region of the contact strips 14a-d. This is important to prevent the formation of deposits, in this case deposits of graphite.

As shown in Figure 4, the part of the insert card 10 which comes into contact with the curves 38 should be without the contact strips 14a-d so that there is no electrical contact but only clamping in this region.

At the opposite end the bends 36 of the contacts 26 protrude into a corresponding recess 44 of the part 22 of the adaptor 20, the bend 36 being contacted on the connection side by a plug part 46 of an analysis device (which is not shown) as soon as the plug part 46 is inserted into an appropriate corresponding opening 48 of the adaptor 20, as is'shown in Figures 3 and 4 together.

It is self-evident that the plug part 46 also has four contact surfaces at distances from each other so that there results a continuous electrical connection from the contact strips 14a-d through the contacts 26 to the corresponding contact strips of the plug part 46 and consequently to the insertion card 10 to the analysis device.

The essential advantage of the invention described is that the contact between the insert card 10 and the contacts 26 is made practically without any friction because in view of the arrangement described contact of individual sections of the contacts only takes place at the bends 34 which are only guided against the contact strips 14a-d vertically, as described above. This is particularly important for the sphere of applications demonstrated, where a new insert card 10 must be inserted for each patient. It must be ensured at the same time that there is always an optimum electrical connection especially because the currents transmitted are extraordinarily small. Even small contamination can cause erroneous readings of the measured values. This is obviated by the arrangement in accordance with the invention.

Figure 5 shows another advantageous possibility for the construction of the contacts 26. In order that each contact may not have to be positioned individually in the adaptor 20, it is proposed as'shown in Figure 5 that a single basic element is stamped out and to provide openings 52 in the region of the middle connecting bridge 50. In this manner a single plane element can first be positioned between the parts 22, 24 of the adaptor 20 which are are subsequently joined as described above figure 3).

Tools are then guided by holes (54) which pass through the housing parts 22, 24 and are perpendicular to the contacts 26, which tools sever the remaining sections 56 of the connecting bridge 50 between the individual contacts (26) and simultaneously bend them backwards. Not only are the individual contacts (26) thereby separated from each other, but the backward bending simultaneously provides for additional fixing of the now individual contacts 26 in the adaptor 20.

It is self-evident that the use of the plug-connector/ adaptor described is not limited only to the sphere of applications mentioned. It can be used in all cases where an electrical connection is effected by means of plug elements which are only to be inserted temporarily. These plug elements can also be inserted at one or at both sides of the plug-connector and in the latter case the region around the bend 36 can be constructed in a manner similar to that previously described with regard to the bend 34.

The plug elements can be constructed in any desired manner in addition to the flat shape described, particularly in the shape of a cylinder with axially running contact surfaces. The structure of the other parts must then be adapted appropriately.

Claims

CLAIMS:

1. Adaptor for the transmission of electrical measurement signals from a plug part (10) which can be plugged in on the input side, to a connector part (46) which can be connected at the output side and which has running therein oe or more contacts (26) for connecting electrically the plug part (10) with the connector part (46) and which has the characteristic feature that the contacts (26) are at their end which faces the plug part (10) movable within the housing (22, 24) of the adaptor in such a manner that when the plug part (10) is plugged in, it touches the contacts (26) at a distance from the free end (34) of the contact (26) and when the plug part (10) is pushed in further, guides the free ends (34) of the contact (26) in a perpendicular direction against the corresponding contacts (14a-d) of the plug part (10).

2. Adaptor in accordance with Claim 1 which has the characteristic feature that the contacts (26) have at a distance from the free end (34) of the contact (26) on the plug side a section (38) protruding in the direction of the contacts (14a-d) of the plug part.

3. Adaptor in accordance with Claim 2 which has the characteristic feature that in the unplugged state the sections (38) of the contacts (26) are at a distance from the corresponding inner surface of the housing (24) of the adaptor (20) which distance is slightly smaller than the thickness of the plug part (10) with contacts (14a-d).

4. An adaptor in accordance with one of the Claims 1 to 3 which has the characteristic feature that the contacts (26) have in the housing (22) between their protruding section (38) and their free end (34) a bearing section on the side opposite to the protruding section (38).

5. Adaptor in accordance with Claim 4 which has the characteristic feature that the bearing section is formed by a protruberance (30) running at right angles to the length of the contacts (26).

6. Adaptor in accordance with Claim 4 which has the characteristic feature that the bearing section is formed by a further protruding section running opposite to the protruding section (38) which further protruding section is adjacent to or can be pressed against the corresponding housing part (22).

7. Adaptor in accordance with one of the Claims 1 to 6 which has the characteristic feature that the free ends (34) of the contacts (26) are bent at right angles so that the appropriate surfaces of contact protrude in the direction of the contacts (14a-d) of the plug part (10).

8. Adaptor in accordance with one of the Claims 1 to 7 which has the characteristic feature that the contacts (26) are firmly supported between the plug side end and the connector side end.

9. Adaptor in accordance with one of the Claims 1 to 8 which has the characteristic feature that the contacts (26) are so positioned that they are insulated from each other by ridges (32) running in the direction of the the length of the contacts (26) in the housing (22, 24).

10. Adaptor in accordance with one of the claims 1 to 9 which has the characteristic feature that the housing (22,24) is in two parts.

11. Plug part (10) for insertion in an adaptor (20) in accordance with one of the claims 1 to 10 in the form of an insertion card which has arranged on it at distances from each other one or more contact strips (14a-d) made of electrically conductive material which at their plug side end terminate at a distance from the corresponding free end (10a).

12. A method of constructing an adaptor for the transmission of electrical signals from a plug part which can be plugged in on the input side, to a connector part which can be connected at the output side, the adaptor comprising a housing containing a plurality of contact elements, the method comprising integrally forming the contacts and inserting them in the housing before separating the contacts from each other.

13. A method as claimed in claim 12, in which the contacts are provided with means joining them to each other and the housing is provided with apertures for access to said joining means whereby said joining means may be severed after closure of the housing.

14. An adaptor substantially as hereinbefore described with reference to the accompanying drawings.

15. A method of constructing an adaptor substantially as hereinbefore described with reference to the accompanying drawings.