1.  Field of the Invention
The present invention generally relates to a plug arrangement for a plurality of individual plugs with individual housings, each having at least one contact pin, with the individual plugs being connectable in a holder to form a uniformly manipulatable plug.  More particularly, plug arrangements are provided for the connection of body electrodes to medical diagnostic and treatment equipment. 
2.  Background Description
Plug arrangements for a plurality of individual plugs with individual housings are known, for example, from DE 30 12 174 C2 and DE 38 07 645 A1.  The individual plugs, which have essentially rectangular individual housings, are inserted or pushed into holders that are open on both sides in the lengthwise direction.  By virtue of a positive connection between the holder and the correspondingly designed individual housings of the individual plugs, the individual plugs are locked in the holder in the lengthwise direction.  In the embodiment disclosed in DE 38 07 645 A1, the individual plugs have grooves that are flush with one another, into which a foldable rib of the otherwise one piece holder engages to insure axial locking. 
In the embodiment according to DE 30 12 174 C2, the holder is provided with specially shaped chambers, to whose shape the outside contour of the individual housings of the individual plugs is adapted.  The holder has a foldable lid.  When the lid is open, the individual plugs can be inserted from above into the chambers of the holder. 
With the known plug arrangements, it is possible to connect the individual plugs to form a uniformly manipulatable plug arrangement, which can be inserted into a uniform matching piece.  According to DE 38 07 645 A1, the holder has a tab pointing in the insertion direction, said tab cooperating with a matching recess in the matching piece to produce protection against twisting.  The locking of the plug arrangement in the matching piece is accomplished by locking grooves which are formed on the contact pins of the plug arrangement and cooperate with matching locking elements in the matching piece. 
While the type and dimensions of the contact pins of individual plugs have been standardized for many applications, there is no such uniformity for the dimensions of the individual housings of the individual plugs, 50 that the matching parts (generally device plugs) into which the plug arrangement is intended to be inserted, have different distances between the contact sets of the individual plugs, since the matching pieces are provided for differently dimensioned individual housings. 
This means that different cable sets must be used with the individual plugs for the various matching pieces, for example, for different device plugs from different medical equipment manufacturers.  If the cable sets are on body electrodes, this results in a considerable stocking cost for using body electrodes with medical equipment from different manufacturers.  In practice, this problem arises for AAMI plugs which have been standardized as far as the contact arrangements of the individual plugs are concerned, for which plugs the various equipment manufacturers have provided contact spacings of different sizes in the bushings that form the matching pieces. 
For using the plug arrangements mentioned hereinabove in conjunction with body electrodes, provision is also made such that the individual plugs, corresponding to the placement of the corresponding body electrodes on the body, have certain, different colors.  Consequently, the individual plug housings must be made from materials with different colors, which naturally increases the manufacturing cost.