Note: Descriptions are shown in the official language in which they were submitted.
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Device having a spherical element to be crimped, crimping
method and crimping system
Technical field of the invention
The invention relates to a device having a spherical element
to be crimped comprising a stem ending at a first end with a
spherical element. The invention also relates to the
associated crimping method and crimping system.
State of the art
A device having a spherical element comprises a stem equipped
at a first end with the spherical element having, for example,
the shape of a bail.
A first example of such a device having a spherical element is
illustrated in Figure 1 and comprises a stem 1 successively
provided along the longitudinal axis Al of the stem with a
spherical element 2, a bearing element 3, and a cylinder 4.
This device having a spherical element is intended to be
crimped onto a plate comprising a through hale, the end of the
stem formed by the cylinder 4 is inserted into the hale in the
plate until the bearing element 3 cames into contact with the
plate. The dimensions of the hale in the plate is
complementary to those of the cylinder 4 of the stem 1 sa that
the bearing element 3 abuts against the plate. Then, the
cylinder 4 is deformed sa as to form a bead whose dimensions
are superior to the diameter of the through bore in the plate,
and thus to crimp the device having a spherical element onto
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the plate. This technique presents the disadvantage of
requiring the access to the two opposite sides of the plate
where the device must be crimped, a first side being used for
inserting the device, and a second side allowing the
deformation of the stem of the device in order to crimp it.
A second example of such a device having a spherical element
is illustrated in Figure 2. This device having a spherical
element differs from that in Figure 1 in that the cylinder 4
of the stem 1 is threaded. This thread makes it possible to
fix the device having a spherical element to a nut once
inserted into a hole in the plate. This technique presents the
disadvantage of requiring several steps for the operator
having to fix the device having a spherical element, in
addition to an access to the two sides of the plate.
Moreover, screwing is not as reliable as crimping as regards
mechanical resistance. For example, if the device having a
spherical element is screwed on a boit on a plate subjected to
important vibrations, it can result in an undesired unscrewing
of the device having a spherical element, and thus in the
dissociation of the device having a spherical element from the
plate.
Devices having a spherical element are used in many fields.
They are found at the fixation interfaces for jacks used for
facilitating the opening of elements such as car hatchbacks,
doors, trunks, etc.
30Object of the invention
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The objective of the invention is to provide a device having a
spherical element whose assembly can be carried out blindly,
i.e. without having to access to the two sides of the plate to
which said device having a spherical element must be fixed.
This objective is reached by the annexed claims and in
particular in that the device comprises a sleeve into which
the stem is inserted, said sleeve successively including along
its longitudinal axis:
- an assembling area for assembling the sleeve on the stem,
- a recessing area intended to the formation of a crimping
bead, and
- a bearing flange, the spherical element of the stem
projecting at the bearing flange.
The invention also relates to a crimping method for crimping a
device having a spherical element with a support comprising a
hale. The method comprises the following steps of:
- inserting the device having a spherical element into the
hale in the support, through its end opposite the spherical
element until the bearing flange cames into contact with the
support,
- crimping the device by applying a holding force sa that the
bearing flange presses on the support, while applying a
traction to the spherical element sa as to deform the sleeve
in the recessing area in order to form a bead.
The invention also relates to a crimping system for a device
having a spherical element to be crimped comprising a stem
mounted in a sleeve and ended at one end with the spherical
element, said system comprises:
- an anvil intended to bear on a bearing flange of the sleeve,
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- means of traction comprising a system of jaws configured to
enclose the spherical element.
Brief description of the drawings
Other advantages and features will more clearly arise from the
following description of particular embodiments of the
invention given as nonrestrictive examples and represented in
the annexed drawings, in which:
Figures 1 and 2 illustrate two types of distinct devices
having a spherical element according to prior art.
Figure 3 illustrates a sectional view of a device having a
spherical element according to an embodiment of the invention.
Figure 4 illustrates a stem having a spherical element as used
in the device in Figure 3.
Figures 5 and 6 respectively illustrate another embodiment of
the device having a spherical element and its associated stem.
Figure 7 illustrates a step of a crimping method for crimping
the device having a spherical element in Figure 3 onto a
support.
Figure 8 illustrates the device having a spherical element
placed on a support once crimped.
Figure 9 illustrates a three-dimensional view of a crimping
system for a device to be crimped, in which one jaw of the
means of traction and a moving part of the anvil have been
removed.
Figure 10 illustrates a three-dimensional view of the crimping
system in Figure 9 in which the removed jaw has been added.
Figure 11 illustrates a view centered on a jaw of the crimping
system.
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Figure 12 illustrates a three-dimensional view of the crimping
system in Figure 10 in which the moving part of the anvil has
been added.
Figure 13 illustrates a locking element mounted on the body of
the anvil in Figure 12.
Figure 14 schematically illustrates two jaws of the means of
traction in an open position.
Figure 15 schematically illustrates two jaws of the means of
traction in a closed position.
Description of preferential embodiments
In Figures 3 to 6, the device having a spherical element to be
crimped comprises a stem 1 ended with a spherical element 2.
This stem 1 is mounted, preferably at a second end opposite
the spherical element 2, onto a sleeve 5 whose body has a
deformable part. Preferably, the sleeve 5 forms a barrel open
at its two distal ends along its longitudinal axis A2, said
longitudinal axis A2 being then collinear with the axis of the
through or unthrough hole forming the sleeve 5.
The stem 1 is inserted into the sleeve 5. The sleeve 5
successively includes along its longitudinal axis A2 (Figures
3 and 5) an assembling area 6 for assembling the sleeve 5 onto
the stem 1, a recessing area 7, and a bearing flange 8. The
bearing flange 8 preferably projects on the entire external
perimeter of the sleeve 5. The spherical element 2 of the stem
1 projects out of the sleeve 5 at the bearing flange 8. In
other words, the sleeve 5 comprises at one of its ends the
bearing flange 8, and the spherical element 2 projects out of
the flange 8 in a direction substantially parallel to the
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longitudinal axis A2 of the sleeve 5 so that the spherical
element can be gripped.
The recessing area 7 is intended for the formation of a
crimping bead, it is thus deformable. In other words, the
recessing area 7 can be made out of a material more malleable
than that forming the assembly area 6 and the bearing flange 8.
According to a preferred particular case, illustrated in
Figures 3 and 5, the sleeve 5 is formed out of only one
material. In this case, the material thickness in the
recessing area 7, in a direction Dl perpendicular to the
longitudinal axis A2 of the sleeve 5, and according to the
revolution of Dl about the longitudinal axis A2 of the sleeve
5, can be inferior to the material thickness in the other
areas of the sleeve 5 (flange 8 and assembly area 9) in the
direction Dl and according to its revolution around the axis
A2.
The stem 1 and the sleeve 5 are preferably made out of a
material chosen among steel, stainless steel, aluminum or
brass.
The sleeve 5 can be assembled with the stem in the assembling
area 6 for example by welding, friction fitting, swaging, or
snap riveting the sleeve 5.
According to a first preferred embodiment, the stem 1,
illustrated in Figure 4, comprises a portion 9, preferably
threaded and forming a first thread. This threaded portion 9
is formed along the body of the stem 1 along its longitudinal
axis Al, preferably at the second end of the stem 1 opposite
the spherical element 2. The assembling area 6, inside the
sleeve 5 (Figure 3), then comprises a second complementary
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thread. The stem 1 is screwingly mounted onto the sleeve 5 in
the assembling area 6. In other words, the first thread of the
stem 1 cooperates with the second thread complementary to the
sleeve 5 made in the assembly area 6.
The assembling area 6 can be swaged onto the external surface
of the sleeve 5. This swaging process allows a work hardening
which fixes the stem 1 definitively to the sleeve 5 while
favoring the fusion of the first and second threads.
According to a variant form, the stem 1 comprises a threaded
portion as indicated above, and the assembling area 9 inside
the sleeve 5 is smooth. During the assembly of the stem 1 with
the sleeve 5, the sleeve 5 is submitted to a swaging process
on its external surface in the assembling area so that the
material of the sleeve 5 flows into the thread of the threaded
portion of the stem in order to look the assembly.
The method for manufacturing the device having a spherical
element to be crimped consists in manufacturing the stem 1 and
the sleeve 5 separately, then in assembling them. Preferably,
before their assembly, the sleeve 5 and the stem 1 are treated,
in particular by an anti-corrosion surface treatment. The
device having a spherical element to be crimped thus obtained
is a product ready to be used, which has a good resistance to
corrosion, because its two constitutive components, namely the
stem 1 and the sleeve 5, were treated separately.
More generally, the assembly can be carried out by inserting
the second end of the stem 1 opposite the spherical element 2
through Lhe end of the sleeve 5 comprising the flange 8, then
by fixing them to one another in the assembling area 6 by
screwing or any other assembling means.
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As in Figures 3 to 6, the stem 1 can comprise a bearing
element 3 between the spherical element 2 and a portion 9 of
the body of the stem 1 (portion threaded or flot) intended to
face the assembling area 6. This bearing element 3 allows
advantageously, for a given stem 1 and sleeve 5, to ensure
that the assembling area 6 faces the corresponding portion 9
of the stem 1 (Figures 3 and 5). Indeed, during the assembly
of the stem 1 with the sleeve 5, the bearing element 3 cornes
into contact with a corresponding bearing area, for example
formed by a shoulder inside the sleeve 5 in Figure 3 or on the
bearing flange 8 in Figure 5, ensuring the correct positioning
of the stem 1 with the sleeve 5 for the assembling, for
example swaging, process. The embodiment in Figure 3 will be
preferred because it makes it possible to hide the bearing
element 3, according to this embodiment the stem can have,
from the spherical element 2, a first diameter then a second
diameter inferior to the first diameter. The change in
diameter allows the bearing on the shoulder of the sleeve.
In fact, the bearing element 3 and the associated bearing area
work as alignment means for aligning the sleeve 5 with the
stem 1, so that they can be more easily shop-assembled.
Consequently, any other alignment means could be used by a
person skilled in the art.
As illustrated in Figures 5 and 6 according to a second
preferred embodiment, the stem 1 can comprise, on the external
surface of its body at the second end of the stem opposite the
spherical element 2, a portion 9, preferably knurled and
intended to firmly fix the stem 1 to the sleeve 5 in the
assembling area 6. The knurled portion 9 comprises a plurality
of longitudinal slots preferably parallel to the longitudinal
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axis Al of the stem (Figure 6) and formed on a first thread of
the stem 1 so as to form a plurality of helical slots, the
first thread cooperating with a second thread of the sleeve 5
formed in the assembling area 6. In Figure 5, the knurled
portion 9 faces the assembling area 6 of the sleeve 5 when the
device is assembled, and can be extended under a part of the
recessing area 7 of the sleeve 5. This extension can be used
for checking the good placement of the stem 1 and the sleeve 5
once assembled. It can be used in combination or not with the
alignment means previously described. Preferably, the sleeve 5
and the stem 1 are then definitively fixed to one another by a
swaging process.
The function of the helical slots, formed by the
characteristic intersection of the thread of the stem 1 and
the longitudinal slots, is to optimize the assembly of the
sleeve 5 on the stem 1. The longitudinal slots ensures an
anti-rotation effect of the sleeve 5 on the stem 1 and the
helical slots ensure an anti-extraction effect of the sleeve 5.
Thus, the knurled portion 9 ensures a good mechanical
resistance of the device once crimped.
According to a variant form of the assembly applicable to the
embodiments and their variants, the sleeve 5 is open at its
two distal ends along its longitudinal axis A2. The stem 1 is
inserted through the bearing flange 8 until its second end,
opposite the spherical element 2, projects over the sleeve 5
at the end of said sleeve 5 opposite the flange 8. Then, this
second end of the stem 1 can be deformed sn as to form a head
10 (Figure 5) whose dimensions are superior to the dimensions
of the section of the sleeve 5, at its end opposite the
bearing flange 8, in a plane perpendicular to the longitudinal
axis A2 of the sleeve 5. Thus, the head 10 of the stem 1 bears
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on a supporting surface 11 of the sleeve 5 in the assembling
area 6. For example, the supporting surface 11 is formed by
the end of the sleeve 5 opposite the bearing flange 8. This
head 10 makes it possible to limit the risks of pulling out
the stem 1 when or after crimping. The risks of pulling out
can still be improved by combining this variant form with the
first or the second preferred embodiment, in particular in
combination with a swaging process.
In a particular case where the dimensions of the spherical
element 2, and a part of the stem 1, are inferior to the
internai dimensions of the sleeve 5, i.e. the spherical
element 2 and at least a part of the stem 1 can slide freely
in the sleeve 5, the second end of the stem 1 opposite the
spherical element 2 can comprise a head 10 directly formed
when machining of the stem 1. The dimensions of this head 10
are superior to the dimensions of the section of the sleeve 5,
at the end of the sleeve 5 opposite the bearing flange 8 and
in a plane perpendicular to the axis A2 of the sleeve 5. Thus,
the stem 2 can be inserted, on the side of the spherical
element 2, into the sleeve 5 through the end of the sleeve 5
opposite the bearing flange 8, until the head 10 bears against
a supporting surface 11 of the sleeve 5 in the assembling area
6, and the spherical element 2 projects on the side of the
sleeve 5 comprising the flange 8. Consequently, the head 10 of
the stem 1 bears on the sleeve 5, limiting the risks of
pulling out the stem 1 when or after crimping. The risks of
pulling out can still be improved by combining this variant
form with the first or the second prpfprrp.d pmh,,diment, in
particular in combination with a swaging process.
According to a variant form of the stem 1 equipped with a head
10 or not, the stem 1 comprises a groove 12 (Figures 3 to 6)
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formed in the stem 1, facing the assembling area 6 and filled
with the material forming the sleeve 5. Preferably, if
necessary, the groove 12 is formed between the head 10 and the
knurled portion (Figure 5). The function of the groove 12 is
to improve the assembly of the sleeve 5 with the stem 1, and
to improve the anti-extraction effect of the stem 1, in
particular in the event of swaging the sleeve 5. Indeed,
swaging the sleeve 5 with the stem 1 in the assembling area 6
makes it possible to drive out the material of the sleeve 5 in
the groove 12, which still improves the pull-out resistance of
the stem 1 when or after crimping.
In a general way, as mentioned previously, the assembly of the
sleeve 5 with the stem 1 is carried out by a swaging process.
The sleeve 5 is then crimped by means of two dies on the stem
1 in one or more operations, according to different angles, in
order to reduce the external diameter of the sleeve 5 in the
assembling area 6. When swaging the sleeve 5 on the stem 1,
the material forming the sleeve 5 enters, if necessary, on the
one hand the knurled or threaded portion 9, and on the other
hand the groove 12 so as to fill them. This makes it possible
to work-harden the material in the assembling area 6, the
work-hardened material and the particular design of the stem 1
facing the assembling area 6 make it possible to obtain a
mechanical assembly which is very resistant when the two
components forming of the device are rotating and/or extracted.
The device having a spherical element to be crimped is
particularly appropriate to the car industry, in particular
for forming bail joint couplings, hinges, or elements that can
be snapped into a device having a shape complementary to that
of the spherical element 2.
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The crimping method for a device having a spherical element ta
be crimped, as described above, with a support 13 is
illustrated in Figures 7 and 8. The support 13 comprises a
hale 13a, preferably a through hale, into which the device
having a spherical element is inserted through its end
opposite the spherical element 2 until the bearing flange 8
cornes into contact with the support 13. Of course, in order
that a supporting surface of the bearing flange 8 can corne
into contact with the support 13, the hale 13a of the support
13 has dimensions higher than the dimensions of the sleeve 5,
except for the bearing flange 8, in a plane perpendicular ta
the longitudinal axis A2 of the sleeve 5, and dimensions lower
than the dimensions of the flange 8 in a plane perpendicular
ta the longitudinal axis A2 of the sleeve 5. Then, the device
having a spherical element can be crimped by applying a
holding force (arrows Fi, F2) sa that the bearing flange 8
presses on the support 13, while applying a traction (arrow F3)
ta the spherical element 2 sa as ta deform the sleeve 5 in the
recessing area 7 in order ta form a crimping bead 15. The
force of traction is preferably applied in a direction
opposite the holding force. Indeed, the combination of the
traction and the holding force will bring the assembling area
6 closer ta the support 13 by deformation of the recessing
area 7. In other words, the crimping bead 15 has dimensions,
in a plane perpendicular ta the axis A2 of the sleeve, higher
than the dimensions of the hale in the same plane.
As illustrated in Figure 8, the deformation of the recessing
area 7 forms a crimping bead 15, whose function is to maintain
the device on the support 13. In other words, the support 13
is maiutained between the bead 15 and the bearing flange 8.
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The advantageous sphere or bail shape of the spherical element
2 of the stem 1 makes it possible to facilitate the traction
exerted on it while using for example a system of jaws 14a,
14b intended to enclose the spherical element 2, in particular
at its interface with the remainder of the stem 1. The holding
force can be generated by an anvil (not represented) bearing
against the bearing flange 8, and pushing the bearing flange 8
towards the support 13 when the force of traction is applied
to the spherical element of the stem 1. Preferably, this force
of traction is substantially parallel to the longitudinal axis
of the sleeve 5.
Preferably, the end of the device intended to be inserted into
the hole 13a in the support 13 comprises a chamfer having a
substantially truncated shape, also called pilot taper. The
chamfer facilitates the introduction of the device into the
support.
Such a device and its crimping method allow a crimping process
while having access to only one side of the plate.
The stem and the spherical element are monobloc elements from
the same material.
Advantageously, as illustrated in Figure 3 to 6, the stem 1
comprises a section located between the assembling area and
the spherical element and having a shape converging towards
the spherical element 2. In fact, this section allows to form
a stop during traction in order to limit the crimping process.
In other words, the stem comprises, between the assembling
area and the spherical element, at least one section formed in
such a manner that it operates as a stop during the crimping
process so that the stop cooperates with the anvil for
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stopping the deformation of the sleeve 5. According to an
embodiment, the stop can have the shape of an annular
projection at the stop section of the stem 1, one face of the
projection flushing with one upper face of the bearing flange
8 from where extends a portion of the stem 1 provided with its
spherical element 2.
As mentioned above, a crimping system for a device having a
spherical element to be crimped and comprising a stem mounted
in a sleeve and ending at one end with the spherical element,
can advantageously be used in the crimping method. The
crimping system enables to position the element spherical in a
three-dimensional space in a repeatable and reliable way.
As illustrated in Figure 9, the crimping system comprises an
anvil 101. This anvil 101 is intended to bear on a bearing
flange 8 of the sleeve 5. In fact, in Figure 9, the anvil 101
bears on a face of the flange 8 from where extends the stem
provided, at its free end distal from the flange 8, with the
spherical element 2.
The crimping system moreover comprises means of traction 102
comprising a system of jaws 103 configured to enclose the
spherical element 2. Thus, during the crimping process, the
jaws enclose the spherical element 2 so as to hold the stem
and exert a traction thereon while the sleeve 5 is maintained
in place by means of the anvil 101 bearing on the flange 8.
The term "enclose" means that the jaws siirrund, at least
partially and narrowly, the spherical element so as to contain
it. Thus, the shape of the jaws enables to position the
spherical element in a repeatable and reliable way.
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From the process of crimping a device having a spherical
element to be crimped it ensues a problem of insertion of the
spherical element. Indeed, the spherical element 2 impedes the
insertion of the stem into the crimping system. To solve this
problem, the system of jaws comprises at least two jaws which
are preferentially articulated to one another.
In Figure 10, the system of jaws comprises two jaws 103a, 103b.
In the illustrated example, the two jaws 103a, 103b are in a
closed position. Preferentially, in this closed position, a
face through which the device to be crimped is introduced
comprises an opening 103c dimensioned so as to prevent the
withdrawal of the spherical element arranged inside a main
cavity delimited by the two jaws and into which opens the
opening 103c.
In order to ensure a best hold of the spherical element during
the crimping process, each of the two jaws 103a, 103b
comprises an open cavity 104 (Figure 11) formed to follow, at
least partially, the outlines of the stem and the spherical
element at their junction, the cavities 104 enable the hold of
the device to be crimped, by means of its spherical element,
in the closed position of the jaws 103a, 10b. Thus, when the
jaws 103a, 103b are in the position closed as in Figure 10,
the two open cavities 104 delimit the main cavity mentioned
above. In other words, the two open cavities 104 present a
partial mold of the spherical element and the stem.
When the jaws are in an open position, the angle formed by the
two jaws 103a, 103b is sufficient to enable the insertion of
the spherical element between the two jaws 103a, 103b, and
when the jaws 103a, 103b are in the closed position the system
of jaws comprises the opening 103c dimensioned so as to
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receive a portion of the stem located between the spherical
element and the bearing flange.
Advantageously as illustrated in Figures 9 and 10, the two
jaws 103a, 103b are mounted so as to rotate A4 with respect to
one another in order to define an open position enabling the
insertion of the spherical element between the jaws 103a, 103b
and a closed position in which the spherical element moves in
accordance with the movements of the means of traction 102.
Preferentially, return means (flot represented) are arranged so
as to continuously urge said jaws towards the open position.
The means of traction 102 are preferentially aligned along a
longitudinal axis A3. This longitudinal axis A3 also defines
the direction of the traction, in Figures 9 and 10, it is
parallel to the axis of the stem of the device to be crimped.
The two jaws are installed so as to rotate about an axis A4
substantially perpendicular to the axis A3.
Preferentially, in order to make a compact and efficient
crimping system, the means of traction are translatingly
mounted in the body of the anvil 101 which then forms a sleeve
making it possible to guide the jaws during traction. In
Figure 12, the body of the anvil 101 then comprises
preferentially a fixed part 101a and a movable part 101b,
swivelingly mounted A5 on the fixed part 101a, whose open and
closed positions coincide respectively with the open and
closed positions of the two jaws 103a, 103b (Figure 10). In
fact, when no force is applied ta the anvil, the return means
enable the hold of the jaws in the open position, the jaw 103b
swivelingly mounted on the jaw 103a is in contact with the
movable part 101b of the anvil and the forces exerted by the
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return means are transmitted ta the movable part 101b sa as ta
maintain it with the anvil in the open position.
The swivel pin A5 in Figure 12 is also represented in Figure
10. In Figure 10, this swivel pin is parallel ta the swivel
pin A4 of the jaws.
As illustrated in Figure 12, the jaws (not represented) and
the anvil 101 are in a closed position. In this closed
position, the end face 107 of the anvil coming in contact with
the bearing flange 8 (Figure 9) comprises an opening 108
enabling the stem ta slide when the traction force is applied
ta the spherical element by the means of traction. This
opening 108 is coaxial with the opening 103c of the jaws
mentioned above. The opening 108 can be dimensioned sa as ta
cooperate with the stop section of the stem mentioned above.
Thus, the stop section cames into contact with the anvil
during traction. The traction moment exerted by the means of
traction is calculated sa that, when the stop section bears on
the anvil, the traction either is stopped, or is not
sufficient any more ta deform the sleeve of the device ta be
crimped in the recessing area.
Ta facilitate the closing of the jaws 103a, 103b and of the
anvil 101, there exists a need for locking, if necessary, the
return means in order ta make the jaws 103a, 103 and the fixed
and movable parts 101a, 101b switch into the closed position.
This need can be fulfilled by providing, as in Figure 13, a
lockina element 105 trahqlatingly mr,uni-...d on the outside of
the body of the anvil 101. The locking element 105 includes a
disengaged position in which the jaws and the anvil 101 (via
its fixed and movable parts) are in the opened position, and
an engaged position (Figure 13) closing again the movable part
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101b of anvil 101 onto its fixed part 101a so that the
movement of closing the anvil is transmitted to the jaws in
order to put them into the closed position by compressing the
return means. In fact, as the movable part 101b is swivelingly
mounted on the fixed part 101a, when switching from the
disengaged position to the engaged position the locking
element 105 bears on these two parts so that the movable part
101a is closed onto the fixed part 101b.
According to an embodiment of the return means illustrated in
Figure 14, these return means comprise a spring 106 whose ends
respectively bears on the jaws 103a, 103b, preferentially in
an associated open cavity. It can be a compression spring 106
whose free length is sufficient to open the jaws 103a, 103b so
as to enable the insertion of the spherical element 2 between
said jaws 103a, 103b. In Figure 14 the jaws 103a, 103b are in
the open position and in Figure 15 the jaws 103a and 103b are
in the closed position. In Figures 14 and 15, the open
cavities 104 described above are represented in dotted unes.
In addition to the jaws, the means of traction can comprise a
traction stem integral with the jaws and a motor configured to
translate the stem.
According to an alternative, the system of jaws comprises a
plurality of jaws arranged in the form of segments able to
open radially. This notably enables to adapt the system of
jaws to various diameters of spherical elements.
