Plug connection

The invention provides a separable plug connection comprising a plug member provided with locking wedges and a wedge pusher. That plug connection may constitute a separate part or may be integrated or inserted in units of equipment, machine members etc. The plug connection is radially and axially locked and is non-positively retained and held against rotation. The housing member is provided with axially extending grooves, which receive ribs provided on the outside periphery of the plug member. Resiliently mounted locking members engage actuating forks of the wedge pusher and when the plug member has been forced into the housing snap into and are locked in an annular groove provided at the end of the grooves.

This invention relates to a plug connection, particularly for directly 
connecting units to each other or to hydraulic lines, electric wiring, 
rotary shafts or the like, comprising a housing and a plug member, which 
is locked in the housing, wherein said housing and plug member are sealed 
against each other, e.g., by means of an O ring. 
Plug connections of that kind are known per se and serve to connect 
so-called base bodies, such as valve housings or the like, to compressed 
air or hydraulic lines, as is the case, e.g., with the plug connection 
disclosed in Published German Application No. 29 52 468. 
Pipe joints comprising fittings and union nuts have been disclosed in 
Published German Application No. 23 62 527. Screwable similar means used 
as couplings for pressure lines have been disclosed in German Patent 
Specification No. 31 08 651. Published German Application No. 23 43 811 
shows a quick-connecting coupling for hoselines and pipelines, comprising 
a plug nipple and a receptacle sleeve, which are interfitted and are held 
together by a U-shaped coupling clamp. 
A common feature of said pipe joints resides in that they can be coupled 
and uncoupled only by a plurality of time-consuming manual operations; 
besides, they require considerable space and it is not possible to 
integrate both parts of the plug coupling, i.e., the housing and the plug 
member, in units of equipment. They cannot be used to connect supply or 
drain lines of two units which are juxtaposed or superimposed in direct 
contact with each other. Besides, most of said quick-connecting couplings 
have an excessive number of parts, which involve a high expenditure even 
for the assembling. 
The invention has been conceived in order to remedy that situation. It is 
an object of the invention to provide a plug connection by which various 
units can be connected to each other and to fluid lines, electric wiring, 
rotary shafts etc. and can be disconnected within short time, without a 
need for tools, in a simple and quick manner and by means of automated 
tools used in large-scale production. 
This object is accomplished in accordance with the invention in that the 
plug coupling consists of a housing member, a plug member and a wedge 
pusher, which is adapted to be interlocked therewith and to push locking 
wedges, which are radially movable in apertures of a shell of the plug 
member. The locking wedges each have a rear extension. Extending ribs are 
provided on the outside surface of the shell of the plug member. Guide 
grooves are provided in the plug member between webs for actuating forks 
of the wedge pusher. A slotted snap ring is provided on the wedge pusher 
and has inwardly facing beads adapted to be received in a mating, i.e., 
peripheral cooperating, grooves in the webs of the plug member. 
A bushing is desirably inserted in the central bore. 
The plug member is desirably sealed against the base member by means of 
sealing rings. 
The wedge pusher and the locking wedges suitably desirably consist of 
plastic. 
The housing member desirably consists of plastic. 
The plug member desirably consists of plastic. 
Various advantages can be afforded by the plug connection proposed by the 
invention. In the first place the plug connection is axially and radially 
firmly locked when the plug member has simply been forced into the housing 
member so that the connection can be used to connect various units of 
machines, motor vehicles, aircraft etc. The connection can be unlocked and 
disengaged quickly by a single manual operation. Automatic tools such as 
are used in large-scale production can readily be used to make and 
eliminate such connection. In its effective position the plug connection 
is not only axially and radially locked but is also locked against 
rotation, as is desirable for numerous applications. The axial lock is 
effected by means of movable wedges, which are locked and unlocked by a 
wedge pusher and snap into a peripheral groove of the housing member as 
the plug member is forced into the housing member. The wedge pusher serves 
also to lock the entire connection and depending on the field of 
application can be made in various modifications. A rotation is prevented 
by means of ribs on the outside of the plug member. The seal between the 
housing and the plug member is established by means of conventional rubber 
sealing elements.

FIG. 1 shows a housing member 1 having a central bore for receiving the 
plug member 2. 
The housing member 1 consists of a flange 1a and a cylindrical shell 1b, 
which is formed in its inside surface with grooves 1c, which are open at 
their top and bottom and serve to receive the ribs 2a, which are provided 
on the outside of the plug member 2 and prevent rotation thereof. The 
annular groove 1d serves to receive the locking wedges 3, which move 
radially outwardly as the wedge pusher 4 is forced toward the housing 
member 1 because their rear extensions 3a are movably mounted in the 
recesses 4d of the actuating forks 4c and are thus flanked by the slots 
4f. 
The plug member 2 consists of a molding 2 having a central bore and is 
completed by the wedge pusher 4 pushed onto the plug member and by the 
locking wedges 3. The molding 2 substantially comprises a shell 2e, which 
has ribs 2a for preventing rotation and slots 2b for movably mounting the 
radially movable locking wedges 3. The shell 2e is connected to the 
tubular inner carrier 2g by webs 2f formed with a peripheral groove 2h. 
Inward of the slots 2b, the carrier 2g is formed adjacent to the guide 
grooves 2d with further apertures 2c for receiving the rear extensions 3a 
of the locking wedges 3 in their effective position. 
The wedge pusher 4 has a top rim 4a and under said rim 4a has a slotted 
snap ring 4b. The latter has a circular series of depending staggered 
resilient extensions, which constitute actuating forks 4c for actuating 
the locking wedges 3, the rear extensions 3a of which enter the slot 4d 
and are urged radially outwardly by the wedge-shaped surfaces 4e. The snap 
ring 4b has sections 4g having inwardly facing beads 4h. Sections 4g are 
biased inwardly. 
When the locking wedges 3 have been inserted into the slots 2b and the 
wedge pusher 4 has been inserted into the molding 2, the wedge pusher 4 
has been firmly interconnected to the molding 2 to provide the plug member 
proper 2. That unit consisting of the plug member 2 is then inserted into 
the housing member 1. A bushing 5 can be inserted into the central bore of 
the plug member 2. The plug member 2 is sealed against the base member 2 
by means of sealing rings 6. In the effective position, when the plug 
member 2 has been forced into the housing member 1, the locking wedges 3 
snap into the annular groove 1d adjacent and perpendicular to the grooves 
1c and the inwardly facing beads 4h of sections 4g "snap" into grooves 2h 
against the bias of sections 4g. As is apparent from FIGS. 2 and 3 the 
locking wedges 3 are prevented from springing back. They can be moved out 
of their effective position only by a pull on the plug member 2 (wedge 
pusher 4). 
FIG. 2 shows the plug member 2 before it is forced to its effective 
position in the housing member; that effective position is shown in FIG. 
3. 
When the plug member 2 has been forced into the housing member, the locking 
members 3 are forced outwardly into the grooves 1d of the housing member 1 
and snap into said grooves. For this purpose the locking wedges 3 are 
urged by respective wedge-shaped surfaces 4e of respective actuating forks 
4c provided on the wedge pusher 4 on the outside periphery of the plug 
member. The step 41 of the slotted snap ring 4b serves as a stop and 
indicates that the effective position shown in FIG. 3 has been reached. 
By a pull on the rim 4a of the wedge pusher 4 the wedge-shaped surface 4e 
is moved outwardly so that the locking wedges 3 are released to return to 
their position of rest in the apertures 2b whereas their rear extensions 
3a enter the slots 2c. The entire plug member 2 can be pulled out of the 
housing member 1. 
Instead of being provided with the illustrated members 1a and 2d, 
respectively, the housing member 1 and the plug member 2 may be integrated 
in the units to be connected. For instance, the plug member may be 
connected to a water pump, which is not shown on the drawings, and which 
may be connected to the housing member 1 in a simple manner, simply in 
that the plug member is forced into the housing member, which may be 
integrated in a motor block, which is not shown too, the parts may be 
separated merely by a pulling operation. The plug member 2 cannot 
spontaneously separate from the housing member 1. 
It will be understood that the housing member 1 and the plug member 2 may 
constitute components of other units, machine members, rotary shafts, 
cable end pieces etc. and that the connection may be used as a separate 
connector or adapter.