Multiple plug arrangement with a plurality of individual plugs

A multiple plug arrangement with a plurality of individual plugs with essentially rectangular plug housings and with a holder that receives the plug housings arranged side by side and flush, the holder being closable on its top by a lid, a bottom opposite lid, and side walls connecting the bottom and lid with one another to form a rectangular cylinder being open at its ends, with the holder holding the individual plugs in position in the axial direction by a form fit that is both simple to manufacture and easy to handle, wherein the plug housings have, on their jacket sides pointing toward the bottom of holder, a window-like recess, and where the bottom is provided with projections matching window-like recesses, and where the closed lid holds the plug housings in an active engagement of the window-like recess of plug housing and projection of the bottom.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention generally relates to a multiple plug arrangement with 
a plurality of individual plugs that is both simple to manufacture and 
easy to handle. More particularly, plug arrangements are provided in 
particular for the connection of body electrodes to medical diagnostic and 
treatment equipment. 
2. Background Description 
Multiple plug arrangements are known, for example, from DE 30 12 174 C2 and 
DE 38 07 645 Al, having essentially rectangular plug housings and a holder 
that receives the plug housings arranged flush next to one another and 
with one another; the holder being closable on its top by a lid, and a 
bottom opposite the lid, and side walls connecting the bottom and lid with 
one another to form a rectangular cylinder and the cylinder is open at its 
ends, with the holder holding the individual plugs in position in the 
axial direction by a form fit. 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. 
The securing of the individual plugs in the known holders has 
disadvantages. The design of the holders with specially shaped chambers 
according to DE 30 12 174 C2 is expensive and results in an increased 
width of the entire arrangement, since the walls of the holder are still 
provided between the plug housings, by which walls the form fit 
perpendicular to the lengthwise direction of the individual plugs is 
produced. 
The plug arrangement known from DE 38 07 645 A1 has the disadvantage that 
the individual plugs are pushed into the holder forming a closed 
rectangular cylinder from one open end, and must thus be carefully jointly 
positioned so that the foldable rib can engage in the otherwise closed top 
of the holder in the grooves of the individual plugs that are open at the 
top and are flush with one another. 
Therefore, the known multiple plug arrangements of the types described have 
disadvantages of manufacture and/or handling. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide a multiple 
plug arrangement of the type involving a plurality of individual plugs 
with essentially rectangular plug housings and a holder that receives the 
plug housings arranged flush next to one another and with one another, 
where the holder is closable on its top by a lid, and a bottom is opposite 
the lid, and side walls connect the bottom and lid with one another to 
form a rectangular cylinder that is open at its ends, with the holder 
holding the individual plugs in position in the axial direction by a form 
fit, wherein the plug housings have, on their jacket side pointing toward 
the bottom of the holder, a window-like recess, where the bottom is 
provided with projections matching the window-like recesses, and where the 
closed lid holds the plug housing in an active engagement of the 
window-like recess of the plug housing and the projection of the bottom. 
The present invention avoids the problems of prior multiple plug 
arrangements of the types described in the Background Description herein 
and provides a plug arrangement that is both simple to manufacture and 
easy to handle. 
The multiple plug arrangement according to the invention has the advantage 
that the holder can be opened by the lid so that the individual plugs can 
be inserted from any direction, namely through the open ends, from above, 
or from all intermediate directions. In contrast to the known multiple 
plug arrangements, therefore, the handling advantage is obtained that a 
certain prescribed direction for insertion of the individual plugs into 
the holder does not exist. Furthermore, there is the advantage that each 
individual plug is brought individually into its correct position relative 
to the bottom, with the window-like recess being slid over the projection 
of the bottom. This automatically produces the alignment of the individual 
plugs in which they are flush with one another, with the plug housings of 
the individual plugs being able to abut one another directly with their 
jacket sides that are perpendicular to the bottom of the holder, so that a 
minimal structural width can be obtained. After all the individual plugs 
have been placed in the correct positions, the lid which is preferably 
articulated foldably on one side wall is closed, preferably by a locking 
connection on the opposite side wall. 
It is especially advantageous for the present invention if a locking 
retention of the multiple plug arrangement on a matching piece, for 
example/of a medical device or a device cable, is accomplished not by 
latching contact pins of the individual plugs but by a tab of the holder 
that is arranged to project forward in the insertion direction of the 
individual plugs, with the tab having a locking means with which the 
holder is lockable in the matching piece by latching.

DETAILED DESCRIPTION OF A PREFERRED 
EMBODIMENT OF THE INVENTION 
Referring now to the drawings, and more particularly to FIG. 1, there is 
shown an individual plug 1 with a rectangular housing 2 with large jacket 
surfaces 3 and small jacket surfaces 4 and two contact pins 5. Individual 
housing 2 is at the end of a cable 6 to which individual plug 1 is 
connected. 
FIG. 1a shows a view of the individual plug on large jacket surface 3, and 
FIG. 1b shows a view of a small jacket surface 4. On small jacket surface 
4 is a locking projection 7 which has a sawtooth-shaped contour in the 
form of a barb. 
FIG. 1c is a view of the free end face of individual plug 1 and shows the 
shape of the two contact pins 5, one of which, according to AAMI 
standards, has a round cross section while the other has a square cross 
section. 
FIG. 2 shows a plurality of views of a sleeve 8, which has a rectangular 
cross section and is open at one end face 9. At the opposite end face 10 
the sleeve has through openings 11, whose shape matches the shape of 
contact pins 5. Sleeve 8 likewise consists of large jacket surfaces 12 and 
small jacket surfaces 13, while FIG. 2a shows a view of a large jacket 
surface and FIG. 2b shows a view of a small jacket surface. The small 
jacket surface 13, toward which the view in FIG. 2b is directed, has a 
window-like through opening 14 whose size matches the size of locking 
projection 7 of individual housing 2. Through opening 14 is sloped toward 
the outside and forms an outer window surface 15 that is larger than the 
inwardly directed window surface formed by through opening 14. 
FIG. 2a and the views in FIG. 2c of end 10 and in FIG. 2d of end 9 show 
that sleeve 8, on a small jacket surface 13 that is not provided with 
through opening 14, has a projection 16 formed by a step toward end 9. 
FIG. 3 shows in an enlarged and cut-away view that through opening 14 is 
sloped toward the outside and has a window area that is larger on the 
outside. 
FIG. 4 shows three views of individual plug 1 with sleeve 8 snapped on. The 
position of contact pin 5 defines an insertion direction pointing toward 
the free end of contact 5 and shows that projection 16 of sleeve 8 is 
located at the rear in the insertion direction. 
In particular, the enlarged detail shown in FIG. 5 shows that locking 
projection 7 of plug housing 2 extends only up to the step in through 
opening 14, in other words it does not project through into the area of 
enlarged window area 15. Locking projection 7 prevents inadvertent 
extraction of individual plug 1 from sleeve 8. Further insertion of 
individual plug 1 in sleeve 8 is prevented by end wall 10 provided with 
through openings 11 but is otherwise closed. 
FIG. 6 makes clear that in the embodiment shown, five individual plugs 1 
with individual plug housings 2 can be assembled into a compact block, in 
which the individual housings with locked sleeves 8 abut one another by 
the large jacket surfaces 12 and are assembled flush with one another. 
In the embodiment shown in FIG. 6, individual plug 1 can be received by the 
holder 17 shown in FIG. 7, and thus, become a uniformly manipulatable plug 
arrangement. 
Holder 17 consists of a bottom 18, two side walls 19, and a lid rib 20 
articulated foldably on one side wall 19, said rib being lockable by a 
locking nose 21 in a recess 22 in the other side wall 19 when the lid 20 
is in the closed position. The holder is open at both end walls 23 and 24. 
The articulation of lid 20 on side wall 19 is made possible by a toothed 
design of the two parts and the insertion of a hinge pin 25. 
FIG. 7a shows a top view of the open end wall 23 with lid 20 in a partially 
opened position, FIG. 7b is a top view of side wall 19 provided with 
recess 22, and FIG. 7c is a top view of side wall 19 provided with hinge 
pin 25. 
FIG. 7d is a top view of lid 20 which in the embodiment has markings in the 
form of letters and/or color identification for the transmission channels 
formed by individual plugs 1. 
The axial immobilization of individual plugs 1 in holders 17 is performed 
by elevations 26 on bottom 18, whose size and position are selected so 
that they engage the large window opening 15 of through opening 14 in 
sleeve 8. Since the height of side walls 19 is adjusted to the height of 
the large jacket surface 12 of sleeve 8, sleeve 8 is thus held in place 
after lid 20 is closed. 
On bottom 18, further in the forward insertion direction, in other words in 
front of end wall 23, a tab 27 is centrally mounted and projects, said tab 
having a locking bead 28 pointing downward. Tab 27 serves both for 
nonrotatable positioning of the plug arrangement and also for axial 
engagement of holder 17 and thus of all individual plugs 1 in holder 17, 
in the correspondingly designed (not shown) matching piece into which the 
plug arrangement is plugged. 
The axial immobilization of the individual plugs in the matching piece is 
thus not effected by individual plugs 1 or their contact pins 5, but by 
the tabs 27 mounted on holder 17. 
FIG. 8 shows views identical to those in FIG. 7 of a holder 17' which is 
provided to hold only three individual plugs 1, but otherwise is 
constructed completely identically to holder 17. FIG. 8d shows that holder 
17' can also cooperate with a matching piece that is suitable for 
receiving a multiple plug arrangement with holder 17, in other words with 
five individual plugs 1. Then only channels A, B, C of the matching piece 
are occupied with holder 17'. The correct positioning of holder 17' in 
such a matching piece is ensured by tab 27. 
Although the invention has been explained with reference to a preferred 
embodiment in which individual plugs (1) in each case are surrounded by 
sleeves (8), whereby uniform individual plugs (1) can be adapted to 
different matching pieces from different instrument manufacturers, and 
color coding is also not necessary by means of the individual plugs (1), 
but can be accomplished using the economical sleeves (8), the present 
invention can of course be achieved in the same fashion by the plug 
housings (2) of the individual plugs (1) themselves having the window-like 
recess (15). 
While the invention has been described in terms of a single preferred 
embodiment, those skilled in the art will recognize that the invention can 
be practiced with modification within the spirit and scope of the appended 
claims.