Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Pressing Tool for Pressing a Cylindrical Pressing Member or a
Pressing Member Comprising a Cylindrical Pressing Portion Onto a
Round Profile
The present invention generally relates to a pressing tool for
pressing a cylindrical pressing member or a pressing member
comprising a cylindrical pressing portion onto a round profile
and onto a pipe conduit in particular.
Such pressing tools are used for press-connecting pipe conduits
with connection pieces or the like, so-called fittings, for
press-connecting cable lugs and connectors with electrical con-
ductors (solid profiles) and for similar purposes. The term
'Iround profile" as used herein is meant to comprise hollow pro-
files as well as solid profiles. A solid profile, for example,
can also be a wire rope.
When~press-connecting a pipe conduit onto the support body of a
fitting by means of a pressing member surrounding the pipe con-
duit, the main aspect is the tight connection between the fit-
ting and the support body thereof, respectively, and the pipe
conduit after the press-connecting procedure. The pressing mem-
ber is three-dimensionally deformed during the press-connecting
procedure. While the fitting and the pressing member may be made
of metal, the pipe conduit may altogether consist of plastic
material or be a multi-layered composite pipe having two plastic
layers of preferably crosslinked polyethylene and a metal layer,
e.g. of aluminum, which is arranged therebetween and serves as
diffusion barrier. On the one hand, such multi-layered composite
pipes have the properties (flexibility) of a plastic pipe and,
on the other hand, the properties of a metal pipe as far as the
diffusion barrier iB concerned. The demands on press-connecting
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cable l~gs and connectors t~ith electrical conductors are inas-
much comparable with the demands on the tightness o~ a pipe
conduit connection as a positive and non-positive connection
between the electrical conductor and the cable lug or the con-
nector, respectively, is to be established.
From DE 34 23 283 A1, a pressing tool of the afore-mentioned
kind is known which comprises two lever arms being supported
between two housing parts so as to be rotatable about two axes
arranged in parallel. At both sides of the fulcrums, one holding
end section and one actuating end section, respectively, extend
from both lever arms. Substantially, the two lever arms can be
aligned so as to be parallel to each other. Two press dies are
arranged at the two holding end sections. One press die, respec-
tively, is supported at a holding end section so as to be rotat-
able about an axis being parallel to the rotational axes of the
lever arms. The two press dies comprise substantially semi-cir-
cular recesses facing each other the peripheral surfaces of
which comprise the pressing surfaces for pressing the pressing
member onto the round profile. In case of lever arms substan-
tially extending in parallel, the two press die recesses form a
closed relief when the two press die surfaces facing each other
abut. The movement of the two lever arms in such a manner that
the two press dies move towards each other is produced by an
axially displaceable hydraulic or otherwise driven piston with
rolls the peripheral surfaces of which can be brought into en-
gagement with the lever arm actuating end section inner surfaces
facing each other. In other wordæ, the two lever arms are simi-
lar to two knee levers, the holding end sections of the two
lever arms, for press-connecting, being moved towards each other
by means of the roll drive- In the known pressing tool according
to DE 34 23 283 A1, the two press dies are actively and control-
ledly guided. Each press die comprises a guide bolt immersed
into a guide groove in one of the two housing parts. Due to this
controlled guidance, the construction of the known pressing tool
is rather complicated.
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From EP 0 452 791 A1, a pressing tool is known in which the
holding members holding the press dies are supporLed, via a
guiding member, on t~Jo lever arms in a controlled manner. With
this pressing tool, it is difficult to guide the parts to be
press-connected in a centered manner. Without such a centered
guidance, tilting may occur which makes an exact press-connec-
tion impossible.
From EP 0 504 490 A1, a tool having three press dies is known,
wherein che two press dies are fixedly and rigidly connected to
the lever arms. The third press die is stationarily supported on
the member connecting the two lever arms.
Finally, from US-A-3 575 036, a pressing tool is known wherein
the four press dies are individually pivotably supported and
pivot about their pivotal axes a~ainst the parts to be press-
connected during press-connection.
It is the object of the invention to provide a pressing tool for
pressing a cylindrical pressing member or a pressing member com-
prising a cylindrical pressing portion onto a round profile,
which ensures a reliably non~positive and positive press-connec-
tion while having a relatively simple construction.
In order to solve this object, the invention suggests a pressing
tool of the afore-mentioned kind comprising two lever arms being
rotatably supported and comprising one holding end section and
one actuating end section, respectively, between which the lever
arms are rotatably supported, and wherein a plurality of press
dies,for pressing the pressing member from all sides onto the
round profile are provided, the press dies comprising pressing
surfaces adapted to abut the pressing member during a press-
connecting procedure, and wherein two press die holding members
for respectively holding at least one press die are provided,
the two press die holding members being rotatably supported at
the holding end sections of the two lever arms without any con-
trolled guidance.
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At the holding end sections of the two lever arms of the pres-
sing tool according to the present invention, press die holding
members are rotatably supported, at which, respectively, at
least one press die, preferably more, particularly two press
dies, are expediently exchangeably supported. Thus, holding
members and press dies are preferably separate elements. The
only connection between the press die holding members and the
pressing tool is the rotatable support of the press die holding
members at the holding end sections of the lever arms. According
to the invention, no provision is made for a controlled guidance
or controlled movement of the press die holding members relative
to the lever arms upon pivoting the lever arms for the purpose
of pressing or opening the pressing tool. The pressing tool
according to the invention is rather configured such that, dur-
ing the press-connecting procedure, the two press die holding
members move centrically towards the pressing member. This hap-
pens automatically, since their press dies or the pressing sur-
facas thereof, respectively, abut the pressing member. Due to
the fact that these pressing surfaces abut the peripheral sur-
face of the pressing member, an automatic centering is effected
without there being any need for a controlled guidance of the
press die holding members. This means that even with a simple
construction (the press die holding members are only rotatably
supported at the lever arms), a reliable press-connection is
ensured since the press die holding members are always moved
towards the pressing member in a centered manner.
The pressing tool according to the invention can be realized
with lever arms being parallel to each other, i.e. with knee
levers, as well as with two lever arms crossing each other and
being rotatably supported, relative to each other, in their
crossing point. The clearance of the rotational movement of the
press die holding members is to be configured such that, during
the entire press-connecting procedure, i.e. with their pressing
surfaces abutting the pressing member, the press die holding
member5 can turn relative to the holding end sections of the
lever arms so far that they are always radially moved onto the
pressing member. Furthermore, it should be possible to pivot the
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press die holding members in the opened state oî the pressing
tool so that the pressing tool can be opened in order to encom-
pass a fitting to be press-connected.
In an advantageous development of the invention, the press dies
are displaceably supported at the press die holding members. At
least two press dies are supported at at least one of the two
press die holding members so as to be displaceable in a direc-
tion extending under an angle which is not zero with respect to
the movement of the pressing surfaces of the press dies during
the press-connecting procedure. Preferably, at least two press
dies are respectively displaceably supported at both press die
holding members. In case of cylindrical pressing surfaces, it is
particularly advantageous to support the press dies at the press
die holding members so as to be displaceable in a direction
being tangential to the pressing surfaces. The advantage of the
displaceable support at their press die holding members consists
in that the pressing surfaces of the press dies are always ra-
dially moved towards the pressing member during the press-con-
necting procedure, i.e. during the centered movement of the
press die holding members towards the pressing member. This
results in an optimal press-connection of the pressing member
with the pipe.
Preferably, the press dies of each press die holding member are
arranged such that they are arranged at a mutual angle of 90.
The press die holding members respectively comprise a V-shaped
recess in whose side flanks extending orthogonally with respect
to each other the press dies are displaceably arranged. In the
press-connecting position of all press dies, these are offset
from each other by 90.
During the press-connecting procedure, the press dies are pre-
ferably moved into the displacement direction against the bias
force of springs; in other words, the press dies are, at the
beginning of a press-connecting procedure, spring-biased into
their original position, i.e. into their start position. While
the press dies, in their original position, are spaced from
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their neighbors, they abut in their press-connecting position
and form a substantially closed press die ring.
In an advantageous development of the invention, it is provided
that the pressing surfaces of the press dies are configured such
that they are already in contact with the pressing member to be
pressed on when their press dies are in their original posi-
tions. Naturally, this contact cannot be brought about over the
entire pressing surface, since the radius of the convex pressing
surfaces is smaller than the radius of the pressing member prior
to the press-connection. Since the difference between the radii,
however, is relatively small and preferably in the range of
about 1 mm, the pressing surfaces quasi abut the peripheral
surface of the pressing member. Thus, the contact pressure can
be applied from all sides over the entire peripheral surface of
the pressing memher in the region of the press dies from the
start of the press procedure. This also improves the press-con-
nection.
Principally, the pressing surfaces may have any shape. The press
dies, for example, may be provided with smooth inner or pressing
surfaces facing each other. Advantageously, it is provided that
the press dies comprise line-shaped concave pressing surfaces.
Preferably, they are formed by forming grooves into the smooth
concave pressing surface of each press die, which results in
line-shaped and parallel-extending projections. Advantageously,
the line-shaped pressing surfaces or projections are spaced from
each other when the press dies are in their press-connecting end
position and abut each other with their radial side surfaces.
The line-shaped pressing surfaces cause a groove press-connec-
tion accompanied by contraction of the three-dimensionally de-
formable pressing member. The entire pressing surface, for exam-
ple, is comprised of the inner surfaces of three rings being
formed by the projections on the inner surfaces of the press
dies, which face each other- Squeezing of the material of the
pressing member in the area between successive pressing surfaces
of adjacent press dies does not arise during the press-connec-
tion, since the pressing member material "drains off towards the
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bulges in this area because of inner mechanical s~ress between
the constrictions and bulges.
Advantageously, the line-shaped pre5sing surfaces are adapted to
the configuration of the fitting as far as the relative position
of the projections of the press dies is concerned. Typically, a
pipe conduit fitting consists of a support body onto which a
pipe conduit end is pushed and a pressing sleeve surrounding the
pipe conduit end. When using press dies with the a~ove-described
pressing surfaces, the supporting body of the fitting is provid-
ed with peripheral beads being axially offset with respect to
the projections of the pressing surfaces of the press dies.
Each holding member comprises reception cavities for the press
dies. Advantageously, the reception cavity for a press die is
realized in such a manner that the press die - at its side op-
posite to the pressing surface - comprises a stud or protrusion
insertable into a reception cavity at the holding member and
being guided therein so as to be longitudinally displaceable.
The width and depth of a reception cavity are substantially
equal to the thickness or projecting length of the press die
stud; the length of a reception cavity, however, is greater than
the length of the stud by the amount by which the press die is
displaceable. The press die, which insofar is partially po~
sitively inserted into the reception cavity through its stud, is
reliably held therein while permitting movement.
The springs urging the press dies into their original positions
are advantageously respectively arranged between the facing ends
of the studs of both press dies supported at a holding member
and the reception cavity surfaces being opposite to these stud
ends. The pressure springs press the two press dies of a holding
member apart so that the press dies are spaced from each other
without any stress, i.e. pressing against a pressing member
without any pressure force. The pressure springs are held in
pocket bores of the press die studs.
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AdvantageoUsly, the press dies are lockingly inserted into the
reception cavities of the holding members; thus, the press dies
can be exchanged against other without any difficulty, each
press die being reliably held.
In case of a locking connection between the press die and the
allocated reception cavity, the locking elements are immersed
into longitudinal locking hollows formed in the cavity inner
surfaces, so that the locking elements also have a guiding func-
tion in order to longitudinally displaceably guide the studs and
thus the press dies relative to the respective holding members.
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In an advantageous development of the invention, the pressing
tool comprises at least one fixed guiding element comprising two
open guiding recesses for receiving and axially fixing and guid-
ing a fitting between the guiding recesses in a centered manner
during the press-connecting procedure, which guiding recesses
are substantially oriented towards the holding end sections of
the lever arms and are in alignment with each other. For reasons
of construction, the pipe connection and the pressing tool move
relative to each other during the press-connecting procedure.
Thereby, the distance between the pipe connection and the ful-
crum(s) of the lever arms is changed. Although the amount of the
relative movement is not important, it is nevertheless present.
In order that the parts to be press-connected, i.e. the fitting,
the pipe and the pressing membex, do not change their axial
position relative to each other during the press-connecting
procedure, the pressing tool according to the invention prefer-
ably comprises the fixed guiding element which axially fixes the
fitting and guides it in a centered manner. Without any centered
guide of the fitting, i.e. without any provision for holding or
arranging the fitting respectively in the center of the press
die ring surrounding the fitting, there is the danger of press
die tilting, resulting in an improper press-connection. The
guide recesses are open to the holding end sections, i.e. when
the pressing tool is open, the fitting, which has been introduc-
ed between the press dies along with the pressing member and the
pipe, protrudes with one section being configured for the axial
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fixing into the axial guiding recess which is open t~ the front
end of the pressing tool.
Preferably, the guiding recesses are limited at both sides by
one pair of guiding element guiding projections, respectively,
one outer projection of the fitting, which preferably is con-
figured as a peripheral projection extending over the entire
periphery of the fitting, being held so as to be enclosed bet-
ween the guiding projections of the two guiding recesses in
order to axially fix the fitting. This means that the two guid-
ing recesses of the guiding element surround the fitting at both
axial sides of the fixing or outer projection. Thus, the fitting
is secured against axial displacements as well as guided in a
centered manner, and this during the entire press-connecting
procedure.
Preferably, one guiding element, respectively, is provided at
both sides of the pressing tool. Thus, the pressing tool need
not be turned to secure the fitting by means of a guiding ele~
ment. While the two guiding recesses of one guiding element are
in alignment with each other, in a direction parallel to the
rotational axis of the lever arms, all guiding elements -, i.e.
four guiding elements in this case - are in alignment with each
other and with the press die ring which is closed in the press-
connecting position and is arranged between the two pairs of
guiding recesses. If there are two guiding elements, the press-
ing member can preferably be axially fixed between the inner
guiding elements by preferably arranging the guiding projections
of the inner guiding recesses of the two guiding elements, which
face each other, in the direction of the two fronts of the pres-
sing member and limiting the axial movements thereof.
Hereinafter, an embodiment of the invention is explained in
detail with respect to the Figures, in which:
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Fig. 1 shows a top plan view of the pressing tool in its -
closed state, the roll drive for closing the holding
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arms for the purpose of press-connecting the pressing
member being indicated,
ig. 2 shows a side view of the pressing tool according to
Fig. 1 in the direction of the arrow II,
ig. 3 shows an illustration of the pressing tool similar to
that of Fig. 1, the connecting plate between the two
lever arms, however, being removed in order to clarify
the press dies and the holding members thereof which
are rotatably supported at tha lever arms,
ig. 4 is an illustration of the pressing tool similar to
that according to Fig. 3, but in the opened state,
ig. 5 is a section along the line V-V of Fig. 3,
ig. 6 is a section along the line VI-VI of Fig. 5,
ig. 7 is a section through the pressing tool along the line
VII-VII according to Fig. 1, and
ig. 8 is a section along the line VIII-VIII of Fig. 1.
In the Figures, a knee lever pressing tool 10 for pressing a
cylindrical pressing member or a pressing member comprising a
cylindrical portion onto a round profile, in this case a pipe
conduit, is shown~ The pipe conduit with the fitting, which are
connected posit.ively and non-po5itively by means of a pressing
member, are indicated in the illustration according to Fig. 8.
The pressing tool 10, which is shown in top view in Fig. 1 and
in side view in Fig. 2, comprises two plates 12 being parallel
to and spaced from each other between which two knee levers or
lever arms 14 are rotatably supported. Each lever arm 14 can be
rotated about its own rotational axis, both rotational axes 16
being parallel to and spaced from each other. At both sides,
each lever arm 14 extends beyond its rotational axis 16. The two
sections of the two lever arms 14 extending towards the front
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end 18 of the pressing tool 10 are holding end sections 20 at
hich press die holding members 22 are rotatably supported,
which will be described later on (cf. also Fig. 3). Actuating
end sections 26 forming the second part of the lever arms 14,
respectively, extend from the rotational axes 16 to the rear end
24 of the pressing tool 10. The inner sides of the spaced ac-
tuating end sections 26 of the lever arms 14, which face each
other, comprise conically tapered entry guidance surfaces 28
merging into parallel inner surface portions 30. The entire
structure of the pressing tool 10 is symmetrical to the axis 31
(see the axis of symmetry plotted in the Figs. 1, 3, and 4,
respectively).
The pressing tool 10 is mounted to a hydraulic apparatus (not
shown in the Figures). This is effected by two lugs 32 being
provided with bores 34 in alignment with each other and being
connected to the plates 12 and extending towards the rear end
24. The hydraulic apparatus comprises bores which are in align-
ment with the bores 34 of the lugs 32. A blocking bolt securing
the pressing tool at the hydraulic apparatus can be pushed
through the bores in alignment with each other. The hydraulic
apparatus comprises a hydraulic piston indicated in Fig. 1 at
36, comprising rolls 38. The piston 36 can be advanced in the
direction of the pressing tool lO. Then, the peripheral surfaces
of the rolls 38 come first into contact with the entry guidance
areas 28 of the inner sides of the actuating end sections 26 of
the lever arms 14, which face each other, whereby the actuating
end sections 26 are pivoted apart in the direction of the arrows
40. As a consequence, the two lever arms 14 rotate about their
rotational axes 16 so that their holding end sections 20 exert
force upon each other in the direction of the arrows 42 via the
press die holding members 22. This force in the direction of the
arrows 42 is the press-connecting force with which the pressing
member is press-connected.
When the piston 36 is in its retracting position, the actuating
end sections 26 of the lever arms 14 can be moved towards each
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other in the direction of the arrows 44- Therefore, for example,
a manual force is exerted upon the outer surfaces 46 of the
actuating end sections 22, which face away from each other, for
pressing the actuating end sections 26 together. The lever arms
14 are pivoted in the direction opposite to that of the press-
connection so that the pressing tool 10 assumes the opening
position shown in Fig. 4.
As has already been mentioned and shown in Figs. 3 and 4, one
press die holding member 22, respectively, is supported at the
holding end sections 20 of the lever arms 14, at which holding
member, in turn, two press dies 48 with pressing surfaces 50 for
press-connecting a pressing member are held. The press die hol-
ding members 22 have a substantially V-shaped configuration and
are supported so as to be rotatable about the bolts 52 in the
area of their tips, where the two legs of the V converge. The
two V-shaped press die holding members 22 are respectively pro-
vided with a recess 54 wherein the holding end sections 20 of
the lever arms 14 are arranged (cf. Figs. 3 and 4). As can be
seen from Fig. 4, the press die holding members 22 can be rotat-
ed by several degrees about the bolts 52 relative to the lever
arms 14 or their holding end sections 20, respectively. On the
one hand, the turning range is limited by the fact that the
inner leg of the V-shaped press die holding member 22 abuts the
portion of the allocated lever arm 14 illustrated-at 56. In the
other direction, the pivot range is limited by the fact that the
edge of the recess 54 abuts the upper end of the holding end
section 20.
As has already been mentioned, two press dies 48 are supported
at each press die holding member 22. Per press die holding mem-
ber 22, the two press dies 48 are arranged so as to be offset
from each other by 90 ; the V-shaped press die holding members
22 comprise V-shaped recesses 58 facing each other, the two leg
surfaces of which extend orthogonally with respect to each
other. This means that each press die 48 extends over 90 so
that the four press dies 48, in their closed state, i.e. in the
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state wherein adjacent press dies 48 contact each other, form a
closed press ring~.
In the direction of the double arrows 60, 62, the press dies 48
are displaceably supported at the V-shaped press die holding
members 22. In the direction of the arrows 62, the press dies 48
are spring-biased; without any forces being exerted on the press
dies 48 via the pressing surfaces 50 thereof, the two press dies
48 of a V-shaped press die holding member 22 are spaced from
each other, as shown in Fig. 4.
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According to Figs. 5 and 6, each press die 48 comprises a stud
piece 64 which is immersed in a reception cavity 66 of the press
die holding member 22 when the press die 48 is mounted to the V-
shaped press die holding member 22. In the two side flanks of
the stud piece 64, two longitudinal recesses 68 are milled in
which the ends of two spring-loaded guiding or locking pins 70
are immersed which are secured to the press die holding member
22. Thereby, a locking connection is established between the
press dies 48 and the press die holding members 22. This locking
connection via the guiding pins 70 immersed ln the recesses 68
also guarantees the guidance of the press dies 48 in their re-
ception cavities 46 at the press die holding members 22.
Further, each stud piece 64 is provided with a spring-loaded
element 72 which supports on one of the peripheral surfaces of
the reception cavities 66 and thus provides for the bias of the
press dies 48 in the direction of the arrows 62. As can be seen
in Fig. 5, but also in Fig. 8, the pressing surfaces 50 of the
press dies 48 comprise line-shaped projections 74 between which
grooves 76 are arranged. Thus, a linear-like press-connection is
effected by means of the press dies 48.
The manipulation of the pressing tool 10 is effected as follows.
First, the pressing tool lO is opened by exerting a force for
opening the pressing tool 10 onto the outer surfaces 46 of the
actuating end sections 26 of the lever arms 14. In the opened
state, the V-shaped press die holding members 22 are spaced
apart, the press dies 48 assuming the original position shown in
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Fig. ~. due to their spring-biases- The pressing member indicated
at 78 including the fitting and the pipe conduit (indicated in
Fig. 8) can be inserted into the pressing tool 10 opened accor-
ding to Fig. 4. Subsequently, the force exertion onto the outer
surfaces 45 of the actuating end sections 26 is terminated so
that the lever arms 14 automatically pivot back until all four
press dies are brought into abutment with the pressing member
78. This pivoting back of the lever arms 14 happens automatical-
ly due to leg springs 80 which extend about bolts 82 forming the
rotational axes 16 and support, with their one leg, on one of
the two plates 12, and, with their other leg, on the lever arms
14. The leg springs 80 are shown in Figs. 3, 4 and 7. Moreover,
Fig. 7 shows the assembly of the pressing tool 10, the connec-
tion of the press die holding members 22 with the lever arms 14
or the holding end sections 20 thereof and the connection of the
lever arrns 14 with the plates 12 in particular.
As soon as the pressing surfaces 50 of the press dies 48 are
brought in abutment with the pressing member 78, the actual
press-connecting procedure starts. The piston 36 advances in the
direction of the pressing tool 10, its rolls 38 coming into
contact with the entry guidance areas 28 of the actuating end
sections 26 and pivoting the lever arms 14. The press die hold-
ing members 22 move towards each othe:r, being radially moved
towards the pressing member 78 due to their rotatable support at
the holding end sections 20 of the lever arms 14. Because of the
displaceable support of each individual press die 48, the press-
ing surfaces 50 of the press dies 48 also always move radially
towards the pressing member 78. The press die movement is ef-
fected until the press dies 48 abut in the press-connecting end
position (cf. Fig. 1). Due to the rotatable support of the press
die holding members 22 at the lever arms 14 and the displaceabi-
lity of the press dies 48 relative to the press die holding
members 22, an optimum press-connection is effected since it is
always ensured that the press dies 48 with their pressing sur-
faces 50 are moved in a centered manner and radially towards the
pressing member 78.
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In connection with Fig. 8, a last specific feature of the pres-
sing tool 10 is to be described- As illustrated in Figs. 1 and
2, fork-like guiding elements 84 are connected to the plates 12.
These guiding elements 84 serve for the axial fixing and the
cen~ered guidance of fitting and pressing member during the
press-connecting procedure. To clarify the situation during the
press-connecting procedure, Fig. 8 shows, above the pressing
tool 10 shown in section, a fitting 86 with a pipe end 90 being
pushed onto its support body indicated at 88 as well as the
pressing member 78 arranged about the pipe end 90. The guiding
elements 84 arranged at both sides of the pressing tool 10
serve, on the one hand, for axial fixation and centered guidance
of the sleeve-like pressing member 78 and, on the other hand,
for axial fixation and centered guidance of the fitting 86. Each
guiding element 84 comprises an inner and an outer guiding fork
92, 94, respectively comprising two guiding projections 96 re-
spectively defining a guiding recess 98 therebetween. All four
guiding recesses 98 are in alignment with each other and with
the opening being surrounded by the press dies 48 in the press-
connecting state. Further, all guiding recesses are open towards
the front end 18 of the pressing tool 10. The inner guiding
forks 92 are spaced apart to such a degree that the pressing
member 78 is received therebetween, this means the axial length
of the pressing member 78 is about the same as or a little shor-
ter than the distance of the inner guiding forks 92. The guiding
recesses 98 of the inner guiding forks 92 have about the same
diameter as the inner diameter of the pressing member 78 so that
the guiding projections 96 of the guiding forks 92, i.e. the
"prongs" thereof, abut the front ring surfaces of the pressing
member 78. The distance of the two guiding forks 92,94 of a
guiding element 84 is equal to the axial extension of a periph-
eral projection 100 of the fitting 86; this peripheral projec-
tion 100 is located between the two guiding forks 92,94 of one
of the two guiding elements 84 during the press-connecting pro-
cedure, the guiding projections 96 of the two guiding forks
92,94 of this guiding element 84 abutting both axial sides of
the peripheral projection 100. ~his means that the inner guiding
fork 92 of the guiding element 84, with its side facing the
16
allocated outer guiding fork 94, abuts the peripheral projection
100 and, with its side facing the other inner guiding fork 92,
it abuts the presslng member 78 and surrounds the pipe end 90
being pushed over the support body 88 of the fitting 86 until it
abuts the peripheral projection 100. After the press-connection,
the pipe end is exposed exactly in this area in which it was
surrounded by one of the inner guiding forks 92 during the de-
formation, whereby a visual monitoring for subsequent inspection
is possible.
The arrangement of the peripheral projection 100 of the fitting
86 between the two guiding forks 92,94 of one of the two guiding
elements 84 can also be achieved by a centered guidance of the
fitting 86 during the press-connecting procedure. Due to the
guidance at the respective guiding element 84, the fitting 86
cannot move out of the center of the press die ring during the
press-connecting procedure so that the danger of tilting of the
press dies 48 is eliminated. Further, the guidance system de-
scribed herein permits that the parts to be press-connected are
located exactly in the center of the ring of press dies (cen-
tered guidance). This guidance is made possible by the movement
of the parts to be press-connected in the guiding forks (in the
direction of the extension of the openings thereof). This (lin-
ear) movement is determined by the pressing procedure by the
fact that the movement components of the press die holding mem-
bers 22 predetermine the linear movement of the press bushing,
the fitting and the pipe within the guiding fork openings.
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