A multiple-passage plug-in coupling for releasably connecting hose or pipe ends, the coupling comprising: a first coupling part, nipples on that part, a second coupling part, sleeves in the second coupling part to receive the said nipples, guide projections on one of said coupling parts, corresponding guide recesses to receive the said projections in the other one of said coupling parts, channels in the said projections and the said other coupling part, and a releasable locking member received by the said channels and serving to lock the two coupling parts together.

This invention relates to a multiple-passage plug-in coupling for 
releasably connecting hose or pipe ends. 
The aim of the invention is to provide a multiple-passage plug-in coupling 
which is of simple construction, is compact, and can be used easily and 
reliably even in places which are difficult of access. 
With this aim in view, the invention is directed to a multiple-passage 
plug-in coupling comprising one coupling part provided with nipples which 
are plugged into corresponding sleeves or holes provided in a second 
coupling part, in which one of the coupling parts has guide pins or other 
projections which are received in corresponding guide recesses in the 
other coupling part, and said projections and the said other coupling part 
each have channels which receive a releasably locking member serving to 
lock the two coupling parts together. 
In one advantageous embodiment of the invention, the pins or other 
projections and the corresponding recesses which receive them are disposed 
non-centrally on their respective coupling parts. In addition, the pins or 
other projections are preferably provided with inclined guide surfaces and 
are longer than the projecting portions of the nipples.

The multiple-passage plug-in coupling shown in the drawing is intended to 
releasably connect up to five hose or pipe ends to another five ends. For 
this purpose, five nipples 1 and five nipple-receiving sleeves 2 are 
provided on the two rectangular-shaped coupling parts 3 and 4 
respectively. The nipples 1 have pipe-receiving portions 1a, while the 
sleeves 2 have pipe-receiving portions 2a. When the two coupling parts 3 
and 4 are brought together from the position shown in FIG. 1 to the 
position shown in FIG. 2, the nipples 1 will enter the sleeves 2. 
To guide the movement of the coupling parts towards one another, the 
coupling part 3 has two oppositely-located guide pins 6 which project from 
the flat surface 3a of the said part and are disposed non-centrally 
thereon. The projecting pins 6 have inclined insertion-guiding slopes 6a 
and engage in corresponding guide recesses 7 in the coupling part 4, the 
recesses 7 having inclined walls 7a matching the sloping surfaces 6a of 
the pins 6. In addition, as shown in FIG. 1, the pins 6 are longer than 
the portions of the nipples 1 projecting from the flat surface 4a of the 
coupling part 4 so as to ensure that the coupling parts 3 and 4 are 
exactly centred and guided when they are brought together, before the 
nipples 1 plug into the sleeves 2. 
The pins 6 are formed with through-channels 8 which, when the parts 3 and 4 
have been brought together, open into and are aligned with similar 
channels 9 in the coupling part 4. The two limbs 5a of a releasable 
U-shaped locking member 5 can then be introduced into the channels 8 and 9 
so as to lock the two coupling parts 3 and 4 together. The outer walls 10 
of the channels 9 are interrupted adjacent the guide recesses 7 so that, 
when the U-shaped locking member 5 is pulled back into the position shown 
on the left-hand side of FIG. 3, outwardly-directed latch surfaces 5b at 
the free ends of the limbs 5a abut shoulders 11 formed by the interrupted 
outer walls 10 and thus prevent the locking member from becoming entirely 
detached from the coupling part 4 while allowing the two couplings 3 and 4 
to be separated from one another. When the locking member 5 is pushed 
inwards into the locking position shown on the righthand side of FIG. 3, 
the latch surfaces 5b engage bevelled edges 12 on the pins 6 in a 
resilient manner, thereby holding the locking member 5 against accidental 
withdrawing movement. 
The multiple-passage plug-in coupling described above is therefore of 
simple construction and small dimensions, and is easy to operate. As 
indicated already, the pins 6 are used for centering and joining the two 
parts 3 and 4 together in a foolproof manner, and they also cooperate with 
the locking member 5 to transmit forces from one coupling part to the 
other. 
Prior to the coupling-together of the two parts 3 and 4, the locking member 
5 is pulled outwards until the latch surfaces 5b at the free ends of the 
limbs 5a engage the shoulders 11 formed in the interrupted walls 10 of the 
channels 9. The guide recesses 7 are now free to receive the pins 6. Since 
the pins 6 are disposed non-centrally on the flat surface 3a of the part 3 
and are longer than the projecting portions of the nipples 1, the two 
coupling parts 3 and 4 are centred with respect to one another by the pins 
6 and the recesses 7 before the nipples 1 are plugged into the sleeves 2. 
This prevents the coupling parts from being connected together in the 
wrong way and also prevents the individual hose and pipe connections from 
twisting when they are joined together. 
The coupling is locked by then pushing-in the locking member 5, whereupon 
the latch surfaces 5b of the latter resiliently engage the bevelled edges 
12. This means that the locking member cannot come out as a result, for 
example, of vibration. 
The coupling is eventually disconnected simply by pulling the locking 
member 5 outwards.