Note: Descriptions are shown in the official language in which they were submitted.
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Wedge drive with slider receiving means
The invention concerns a wedge drive or cotter key comprising a
slider element receiving means, a movable slider element and a driver
element, and wherein sliding surfaces are provided between the slider element
to and the driver element, wherein a dovetail-like or prism guide with sliding
surfaces
provided at the driver element and of the slider element receiving means, is
arranged between the slider element and the slider element receiving means.
The
invention furthermore concerns a slider element for a wedge drive with a
slider
element receiving means and a driver element, the slider element being
arranged
between the slider element receiving means and the driver element, wherein the
slider element is provided with a dovetail-like or prismatically formed side
with
sliding surfaces.
A wedge drive which is also referred to as a slider serves basically for
2o diverting pressing forces to stamping or shaping tools in order thereby to
be able to cut, perforate or shape in particular regions of bodywork
portions, which are of an inclined or undercut configuration. In that
arrangement the wedge drive includes at least one slider element receiving
means, a movable slider element and a driver element. The slider element
receiving means which has such as rigid is usually connected to apart of the
press or the pressing tool, in which press or pressing tool the wedge drive
is intended to implement the stamping or shaping operations. A wedge
drive is referred to as an upper part slider if the slider element receiving
means thereof is fixed in the upper part of the pressing tool, which is
connected to the moving pressing ram. Reference is made to a lower part
slider if the slider element receiving means thereof is connected to the
lower pressing tool which is fixed on the rigid press table. Irrespective of
the part to which the slider element receiving means of the wedge drive is
connected, it usually has a linear guide means in which the movable slider
element is reciprocatable, but as such it is fixedly connected to the slider
element receiving means. The driver element is usually in the form of a
rigid element fixedly connected to the part of the pressing tool, to which
the slider element receiving means is not fastened. The driver element
usually has inclined wedge portions and therewith serves as a drive
4o element in relation the movable slider element.
In the situation involving a substantially perpendicular advance
movement of a pressing tool, which is referred to as the working stroke,
the slider element which is in its rearward position comes to bear against
the rigidly standing driver element and supported thereby is advanced by
way of the inclined positioning thereof (wedge shape) facing in the working
direction. In that situation the inclination of the linear guide means of the
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slider element receiving means is matched to the inclined positioning of the
driver element so that no acceleration of the movable slider element is
involved, in relation to the actual pressing speed. The movable slider
element is thus only driven by the pressing tool and urged controlledly
forwardly or outwardly in order to be able to perform the stamping or
shaping work. In the rearward stroke movement in which the pressing tool
has moved beyond its bottom dead center position and the two parts are
moving away from each other again, the movable slider element is usually
pushed back into its original position by means of a suitably designed
1o resilient element, whereupon the procedure can be re-started. The return
force required for the return movement of the slider element is usually
between 2 and 10% of the actual working force and the weight of the slider
element. In that respect, decisive aspects in regard to the magnitude of the
pressing force are the dimensions of the surfaces for transmitting the
pressure, which are referred to as sliding surfaces, the respective
inclinations of the linear guide means in the slider element receiving means
and the inclined positioning of the driver element as well as the cooperation
of the surfaces and inclinations and the structure of the slider
element itself. The pressures to be transmitted are usually between a few
100 kN and several 10,000 kN.
The linear guide means in the slider element receiving means was
intended to guide the movable slider element with as little play as possible
and in so doing to withstand high pressing forces and afford long service
lives. To permit burr-free cutting or perforating of a workpiece a tolerance
in terms of accuracy of movement of the movable slider element of a
maximum of 0.02 mm is required. If that tolerance is not met, the
workpieces which are cut or perforated or shaped in some other way can no
longer be placed one upon the other in accurate register relationship so
that errors in the basic bodywork structure occur and/or workpieces
rubbing against each other means that faster corrosion occurs, the
bodywork constructed is of reduced strength and possibly an increased
amount of noise is generated by virtue of sheet metal parts which come
loose. To avoid all those disadvantages, the requirement in particular in the
automobile industry is that a wedge drive provides for extremely high
levels of accuracy of movement and permanently withstands the pressing
pressures required or makes them available in relation to the stamping or
shaping tool.
In order to afford the required accuracy of movement here, various
concepts have been developed, of which some are set forth hereinafter. By
way of example slider guide means with side sliding plates and driver
elements arranged at a right angle as well as a screwed cover plate for
holding the slider element are known. Slider guide means of that kind
admittedly withstand very high pressing forces and lateral thrust forces but
they are very complicated and costly to manufacture as a high level of
manual co-ordination complication and expenditure is required for matching
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the guide play between the elements. A further problem which has been
found is inadequate protection in regard to the slider guide means falling
apart, in which case the whole of the slider weight plus the rearward
attachment forces act on the fastening screws of the cover plate and can
very rapidly overload them. In addition such a slider guide means is
comparatively large in structural size and is therefore unsuitable for
constructing small sliders.
Slider guide means are also known having lateral angle bars and a
driver plate arranged at a right angle. Unlike the above-discussed slider
guide means the combination of the lateral sliding plates with a cover plate
leads to a reduction in the amount of structural space required so that in
particular it is also possible as a result to construct smaller slider sizes.
It
will be noted however that high forces act on the fastening screws of the
angle bars and as a result provide that there is a relatively high risk of
accident. In addition the complication and expenditure in terms of
coordinating
the co-operating elements for matching the guide play is high so
that additional costs are also incurred here.
A further kind of slider guide which is used includes lateral sliding
and cover plates which are inclined at an angle of 45 . They are therefore
arranged approximately in a roof-shaped configuration. That makes it possible
to achieve a reduction in structural width as the cover bars and the
sliding plates are arranged one over the other and not one beside the
other. It will be noted however that the structural space required is still
very great so that it is scarcely possible to produce small sliders. In
addition the traction forces occurring have a detrimental effect on the
fastening screws of the cover plates, and that leads to a high level of
process uncertainty.
A further known structure includes a slider guide means with a driver
plate and one or two column guide means with bushes in order to hold the
slider element laterally and to prevent it from dropping out. The use of a
guide column with a driver plate means that admittedly only still
comparatively small structural spaces are required and it is possible to
achieve considerably less expensive manufacture than when using the
above-mentioned solutions in the state of the art. It will be noted however
that the column guide means, due to the type of structure involved, is not
capable of compensating for high lateral pressures. In addition it cannot
carry any heavyweight slider elements so that those slider elements
produce less pressing forces and are more susceptible to trouble in the
pressing procedure.
A further kind of slider element guide arrangement is known for
example from EP 1 035 965 61. This arrangement provides for a clamping
embracing relationship in respect of the slider element guide means,
wherein the driver element provides a prism guide and sliding plates are
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inserted between the driver element and the slider element. The roof shape
involved
means that very high slider forces are possible, while entailing small
structural
spaces, and equally a very accurate guide play so that the wedge drive or the
slider
element guide means is stable and has a long working life. It will be noted
however
that manufacture of the clamping guide means, because of the expensive cutting
machining operations required to achieve a precise fitting shape, is really
complicated and cost intensive as a result.
Further wedge drives are also known for example from EP 1259371131, DE 198 60
178 C1 and EP 1 197 319 131.
FR-A-2 421 030 discloses a wedge drive of the kind mentioned in the beginning
of
the description which is used for a work-piece clamping device. The device
comprises a base plate (driver element), a ram (slider element receiving
means) and
a wedge (slider element) located between the base plate and the ram, the wedge
having an inclined surface facing the ram, the facing surface of the ram being
inclined at the same angle, whereby the wedge is driven by a screw along the
base
plate for altering the separation between the base plate and the ram. The
wedge
has a dovetail-shaped projection with sliding surfaces for running in a
corresponding
groove of the base plate.
A wedge drive of the kind indicated in the beginning of the description is
also known
from DE 198 61 171 B4 as a radial press comprising an upper press yoke (slider
element), a transverse pusher (slider element receiving means) having an
inclined
surface facing a correspondingly inclined surface of the upper press yoke. A
dovetail-
like or T-like guide is provided between the transverse pusher and the upper
press
yoke including sliding surfaces.
All the above-described design concepts of a slider element guide means for a
wedge drive have one or more sliding plates for the transmission of generally
high
pressing forces, and likewise suitably designed holding elements for holding
the
slider element in the guide provided for same. The sliding plates serve to
permanently transmit the working pressures exerted by the pressing tool from
the
slider element receiving means and the driver element to the movable slider
element
and thus to guarantee the actual advancing drive effect. The holding elements
serve
for linearly holding the slider element on the sliding plates of the sliding
element
receiving means, in which case they permanently ensure the required accuracy
of
movement and are intended to possibly compensate for lateral thrust forces
which
occur in the shaping operation or in the cutting or stamping procedure.
Now the object of the present invention is to further develop a wedge drive in
such a
way that a guide for the movable slider element is provided, which permits
still
better motional accuracy than the solutions in the state of the art, which
provides
CA 02700576 2011-11-29
for optimum conversion of the pressing force which acts into the stamping or
shaping movement, which compensates for lateral thrust forces even better than
the
state of the art and which provides a longer service life for the wedge drive
than is
hitherto possible with the solutions in the state of the art. The invention
further
5 seeks to provide that a lower level of complication and expenditure is
required when
co-ordinating the wedge drives and more economical manufacture becomes a
possibility.
For a wedge drive, as provided in the present application, that object is
attained in
1o the that the sliding surfaces provided on the slider element, by way of
which forces
are transmitted from the slider receiving means to the slider element in a
work
stroke during which the slider element is moved outwardly between the driver
element and the slider element receiving means, are arranged at an angle
relative to
each other which is bigger than 00 and smaller than 1800.
For a slider element, as provided in the present application, the object is
attained in
that the sliding surfaces provided on the slider element, by way of which
forces are
transmitted from the slider element receiving means to the slider element in a
working stroke during which the slider element is moved outwardly between the
2o driver element and the slider element receiving means, are arranged at an
angle
relative to each other.
That therefore provides a wedge drive or cotter key in which the movable
slider
element has a dovetail-like or prismatic side, wherein the slider element
receiving
means is in the form of a corresponding counterpart portion so that the slider
element with its dovetail-like or prismatic side can engage into the slider
element
receiving means and can be guided and held therein, in the self-centering
manner.
The surfaces on the slider element and/or the slider element receiving means,
that
are respectively provided by the dovetail shape and the prism shape, bear
against
3o each other, in which case forces directed in different directions can be
carried
without any problem by virtue of the surfaces which are at an angle relative
to each
other, in the dovetail or prism shape. This guide means between the slider
element
receiving means and the slider element permits self-centering linear guidance
for the
slider element. The dovetail shape means that, after being inserted into the
correspondingly shaped receiving configuration of the slider element receiving
means, the movable slider element is safeguarded against falling out or
lateral
displacement, without further measures.
As guidance for the slider element along the slider element receiving means by
virtue of the dovetail guide arrangement is possible with a high degree of
precision
and without being sensitive to lateral thrust forces as well as being
inexpensive to
manufacture, without the provision of further components in the form of a
linear
guide means, the result is a compact wedge drive with a very high level of
accuracy
of motion, which is also insensitive in relation to manufacturing tolerances.
As clamp
guides or further elements are no longer required, not only can the costs be
reduced
in comparison with the solutions in the state of the art,
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but the process reliability is also increased and a possible risk of accident
reduced. As the slider element only needs to be pushed into the slider
element receiving means, assembly of the wedge drive is simplified in
comparison with the solutions in the state of the art. It is possible to
dispense with a cost-intensive operation of grinding in the guide elements
as the prism guides or dovetail guide of the slider element receiving means,
the slider element end the driver element are insensitive in relation to
tolerances in manufacture. The self-centering effect achieved by the prism
guides
also leads to a very high level of accuracy in terms of motion in
lo regard to carrying lateral thrust forces. By virtue of the compact
structure
of the wedge drive it is not only suitable for a small structural space
available within a pressing tool, but, as will be appreciated, it is also
suitable for uses involving larger dimensions.
Advantageously sliding surfaces are provided on the slider elements
And or the slider element receiving means. In a particularly preferred
feature the dovetail-like or prism guide means includes at least two sliding
plates arranged at an angle relative to each other. Advantageously the
sliding plates of the dovetail-like or prism guide means can be L-shaped
in cross-section. It is further found to be advantageous if sliding plates are
provided on all surfaces, which slide against each other, of the slider
element and the slider element receiving means, so that in each case at
least two sliding plates arranged at an angle relative to each other are
provided on the slider element and the slider element receiving means. The
sliding plates which are roof-shaped or L-shaped in cross-section can
advantageously be so arranged that their inner narrow sides, by virtue of
the outwardly inclined oblique positioning of the sliding plates, afford an
undercut configuration in the form of the above-mentioned dovetail guide
configuration.
By virtue of the provision of sliding plates at two sides of the slider
element and the slider element receiving means respectively at the same
time, wherein they are arranged symmetrically and in an L-shape or in a
roof shape so that the shape of a dovetail guide means can be achieved, it
is particularly advantageously possible to dispense with further,
costintensive,
linear holding elements. Furthermore, the manufacturing costs
can be markedly reduced in comparison with the solutions in the state of
the art as fewer components are provided than in the state of the art
without in any way adversely affecting the mode of operation of the wedge
drive but rather permitting more reliable and more secure operation
without the provision of holding elements, but with an extremely high level
of motion accuracy.
Advantageously the dovetail-like or prism guide means includes a
positively locking connection between the slider element and the slider
element receiving means. The provision of such a positively locking
connection affords a compact unit, by way of which even high pressing
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forces can be transmitted without any problem. Furthermore that prevents
the slider element and the slider element receiving means from unwantedly
sliding out of each other as the positively locking relationship in the region
of the dovetail or prism guide means and the mechanical contact between
the two portions to be joined of the slider element and the slider element
receiving means provides that the forces to be transmitted are in fact
transmitted by way of the surfaces which are in contact with each other
and which are at an angle relative to each other and in that respect assist
with holding the component parts together, by virtue of their angular
positioning.
It has further proven to be advantageous if the slider element
receiving means is of a protruding configuration in the region of the sliding
surfaces and/or the receiving means of the sliding plates. That provides a
larger surface for the sliding movement of the slider element with respect
to the slider element receiving means so that very good transmission of the
pressing forces by way of those enlarged receiving surfaces is possible.
Advantageously the sliding plates can be releasably fixed to the
slider element receiving means and/or the slider element, in particular by
fixing screws. The releasability of the sliding plates from the slider element
receiving means and the slider element respectively means that it is
possible to replace them when wear occurs. It will be appreciated that in
principle it would also be possible to equip the corresponding sliding
surfaces of the slider element receiving means and the slider element in
such a way that they can silde against each other, without the interposition
of sliding plates. In that case however in the event of wear it would be
necessary to replace the slider element receiving means and the slider
element themselves so that it has proven to be less expensive and in
3o a operation easier in terms of handling if the arrangement has releasable
sliding plates as then replacement thereof is possible quickly and without
any problem.
The side of the slider element, which is of a dovetail-like or prismatic
shape, advantageously has support surfaces as the sliding surfaces, in
particular for the attachment of sliding plates. It has proven to be
particularly advantageous in that respect to provide in each case two sliding
plates which are arranged at an angle relative to each other as here it is
possible to avoid arduous adjustment of four individual sliding plates which
are arranged at an angle relative to each other. It is only necessary to
implement adjustment at a respective one of the support surfaces for a
respective sliding plate so that it is possible to rapidly change sliding
plates.
Advantageously a wedge guide means is provided between the slider
element and the driver element. That arrangement provides that very high
forces can be carried while involving a comparatively small structural
space, while at the same time accurate stable guidance for the slider
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element on the driver element upon movement thereof is possible.
Advantageously the wedge guide means includes two sliding plates
arranged at an angle relative to each other. Those sliding plates
advantageously comprise a material which assists with the sliding
movement, in particular bronze with a solid lubricant. The provision of the
sliding plates which are fastened in particular replaceably to the driver
and/or slider element provides in a simple fashion that the plates can be
replaced in the event of wear while in operation providing for optimum
lo sliding movement of the surfaces, which are joined to each other, of the
driver element and the slider element.
It has further proven to be advantageous if the dovetail-like or prism
guide means and the wedge guide means are provided at an angle relative
to each other on the slider element. The arrangement involving a plurality
of angles relative to each other means that it is possible to reduce in
particular the structural size of the wedge drive, thus affording a compact
unit which can be used even with constricted space conditions within a
pressing tool.
It is further found to be advantageous if the dovetail-like or prism
guide means and the wedge guide means are provided at two mutually
adjacent sides of the slider element. That makes it possible to improve the
accuracy of movement but at the same time primarily also it is possible to
reduce the structural size in comparison with the solutions in the state of
the art which usually involve operative engagement on a driver element
and operative engagement on the slider element receiving means at two
mutually oppositely disposed sides of the slider element.
The slider element can have a third side adjacent to the other two
sides, with a receiving means for receiving a processing tool. In that case
the third side advantageously has at least two undercut configurations
and/or grooves for the insertion of protruding elements of a receiving
means for receiving a processing tool. The provision of such a separate
receiving means for receiving a processing tool such as for example a
perforating punch leads to simple replacement of the tool without any
problem as it is only necessary for the receiving means to be removed from
the third side of the slider element and replaced by another receiving
means which for example carries a different tool. This totally eliminates a
tedious procedure of screwing on and unscrewing the processing tool itself,
possibly with drilling of further holes in the slider element. The provision
of
undercut configurations and/or grooves at the third side of the slider
element means that the receiving means can be inserted there for example
by being pushed into place, in which case further fixing is not even
necessary as optimum transmission of force is already guaranteed in
particular by virtue of the undercut configurations, due to the positively
locking connection afforded thereby.
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The third side of the slider element can also be provided with at least
one wedge surface, in which case the receiving means then preferably has
a corresponding wedge surface to provide a positively locking connection
between the slider element and the receiving means for the processing
tool. Lateral thrust forces can be carried thereby and the transmission of
force can be optimised.
During the working stroke the slider element is moved outwardly between the
lo sliding surfaces, which are arranged in wedge form, of the driver element
and the
slider element receiving means, in which case the slider element receiving
means
and the driver element are movable towards each other perpendicularly, driven
by
the pressing stroke. The pressing force applied by the pressing tool
corresponds in that respect to the counteracting force which the wedge
drive applies for the work done by it, for example cutting, perforating or
post-shaping a bodywork portion, wherein that is distributed to the sliding
surfaces in dependence on the respective angular position of the individual
sliding surfaces relative to each other. Due to the provision of sliding
surfaces which are arranged at an angle relative to each other and which
2o are arranged in a roof shape or a prism shape relative to each other, the
movable slider element is automatically centered between the slider
element receiving means and the driver element or on the sliding surfaces
thereof. That can provide a very high level of motion accuracy and lateral
guidance for the slider element, while manufacturing tolerances or other
inaccuracies caused by manufacture can be compensated and thus no
longer have an adverse influence.
In the return motion of the slider element, referred to as the
rearward strake, in which the pressing tool moves away from each other
3o and thus the slider element receiving means is moved away from the driver
element, the slider element is retracted into the region between the slider
element receiving means and the driver element. The forces acting on the
slider
element in the rearward stroke or in the return motion are restricted only by
the
weight of the slider element and the retraction forces acting on the slider
element
receiving means, the slider element and the driver element, as the pressing
tool
moves apart. The sliding surfaces of the slider element and the slider guide
element, which run against each other in that situation, can be reduced in
their
dimensions in relation to the sliding surfaces which run against each other
in the working stroke, so that the above-mentioned L-shape for the sliding
surfaces on the dovetail guide means is found to be highly suitable in that
respect.
In the case of a suspended upper part slider or wedge drive the
weight of the slider element acts on the surfaces of the slider element
receiving means, which bear in positively locking relationship against the
slider element sliding surfaces of the dovetail guide arrangement, and
exerts a downwardly directed spreading force on those surfaces of the
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sliding element receiving means. By virtue of the positively locking shoulder
support for the slider element with respect to the slider element receiving
means however those lateral thrust forces are compensated so that
permanent and stable fixing of the slider element to the slider element
5 receiving means and the sliding plates on the slider element and the slider
element receiving means is possible. Therefore the fixing screws of the
sliding plates are not subject to any forces such as to damage them, in
particular tensile forces.
lo The prism guide means or the dovetail-like guide means provided between the
slider element and the slider element receiving means can thus be used to
equip
small, medium and large-format wedge drives, thus affording a large range of
uses. Embodiments by way of example will be described in greater detail
hereinafter to describe the invention more fully, with reference to the
drawings in which:
Figure 1 shows a vertical cross-sectional view through a first
embodiment of a wedge drive according to the invention with dovetail-
like guide means,
2o Figure 2 shows a perspective view of the slider element receiving
means and the slider element of the wedge drive of Figure 1,
Figure 3 shows a perspective exploded view of the slider element
receiving means and the slider element of Figure 2,
Figure 4 shows a perspective view of a second embodiment of a
wedge drive according to the invention with dovetail-like guide means
between the slider element and the slider element receiving means,
Figure 5 shows a perspective view of the wedge drive of Figure 4
without a driver element,
Figure 6 shows a perspective side view of the wedge drive of Figure 4,
Figure 7 shows a lateral plan view of the wedge drive of Figure 4,
Figure 8 shows a sectional side view of the wedge drive of Figure 4,
Figure 9 shows a perspective view inclinedly from above of the
wedge drive shown in Figure 4 with fitted receiving means for a
processing tool,
Figure 10 shows a perspective view of the wedge drive provided with
a receiving means for a processing tool as shown in Figure 9 with the
driver element removed, and
Figure 11 shows a perspective view of the wedge drive of Figure 10
with the receiving means for a processing tool removed and with the
driver element removed.
Figure 1 shows a sectional view of a wedge drive 1 or cotter key
comprising a slider element receiving means 2, a slider element 3 and a
receiving means 4 for receiving a processing tool. A driver element
connected to the slider element 3 is not visible in Figure 1 but can be found
in the perspective view in Figure 4.
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The slider element and the slider element receiving means are
connected together by way of a dovetail-like or prism guide means 6. In
this case the slider element 3 has a portion 30 of a dovetail-like
configuration. It includes two sliding surfaces 31, 32, 33, 34 which are
respectively disposed at an angle to each other on both sides. In this
arrangement the two sliding surfaces 31 and 33 are smaller than the two
sliding surfaces 32 and 34. The reason for this is that, in a working stroke,
the pressing forces exerted by a pressing tool in which the wedge drive is
arranged are transmitted from the slider receiving means to the slider
1 o element by way of the sliding surfaces 32, 34. In a return motion or a
rearward strake movement of the pressing tool the slider element is
retracted by way of the two sliding surfaces 31, 33, in which case a very
much lesser force is exerted on the slider element so that those smaller
dimensions for the sliding surfaces are adequate.
The slider element receiving means 2 has a portion 20 which is of a
correspondingly opposite and equal configuration and which includes
corresponding sliding surfaces 21 through 24 which each bear in positively
locking relationship against the sliding surfaces 31 through 34. In addition
the portion 30 of a dovetail-like configuration engages with a protruding
portion 35 into a corresponding recess 25 in positively locking relationship
in the slider element receiving means 2. The protruding portion 35 can only
extend over apart of the longitudinal extent of the slider element and the
slider element receiving means respectively.
In principle it is also possible not to provide such a protruding portion, in
which
case however the hold of the slider element and the slider element receiving
means to each other is markedly improved by such a protruding portion 35 which
engages in positively locking relationship into a corresponding recess 25 of
the
slider element receiving means.
As can further be seen from Figure 1, sliding plates are provided on
the slider element receiving means and the slider element to form the
corresponding sliding surfaces 21 through 24, and 31 through 34
respectively. The sliding plates 26, 27 on the slider element receiving
means 2 are of an L-shaped cross-section in cross-section, whereas
individual flat sliding plates 36, 37, 38, 39 are attached to the
corresponding surfaces of the slider element, as can be better seen from
Figure 3. The L-shaped sliding plates 26, 27 are fixed to the slider element
4o receiving means by fixing screws 28, 29. The sliding plates 36 through 39
are also fixed to the slider element by corresponding fixing screws,
although these are not shown in Figure 1.
The provision of such a releasable fixing for the sliding plates to the
slider element receiving means and the slider element respectively permits
the sliding plates to be replaced without any problem, when wear is
involved. The fixing screws are arranged in sunk relationship in the sliding
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plates so that the sliding movement of the sliding surfaces against each
other is not impeded by the provision of the fixing screws.
As can be clearly seen in particular from the cross-sectional view in
Figure 1 the slider element receiving means protrudes outwardly in the
region of the dovetail-like guide means to provide a sufficiently large
sliding
surface 22, 24 for support and sliding movement on the slider element 3.
As can be further seen from Figure 1 the receiving means 4, for
1o receiving a processing tool, is provided with a T-shaped protrusion 40 and
the slider element 3 is provided with a corresponding T-shaped groove 41.
By virtue of that arrangement the receiving means far the processing tool
can be easily pushed into the T-shaped groove 41, whereby simple fixing
and a secure hold on the slider element is possible. Instead of a T-shaped
groove and a T-shaped protrusion, it is also possible to provide a wedge
shape with corresponding grooves and protrusions in that region so that in
addition it is also possible to provide a centering action and to provide for
carrying lateral thrust forces in that region. As however there is no
provision for movement of the slider element with respect to the receiving
means, in most cases it is sufficient to provide the T-shaped groove and the
T-shaped protrusion.
Figure 2 shows a perspective view of the detail of the slider element
receiving means and the slider element, viewed inclinedly from below. The
two are shown separately so that it is possible to view the sliding plates 26,
27 of the slider element receiving means 2 and the dovetail-shaped portion
20 of the slider element receiving means. In addition it is also possible to
clearly see the portion 30 of the slider element, which is of a dovetail-like
configuration, and also the sliding plates secured thereto, the fixing thereof
3o by screws also being indicated. As can be even better seen from the
perspective exploded view in Figure 3 the respective sliding plates are fixed
to the slider element receiving means and the slider element respectively
by three fixing screws. The sliding plates have corresponding bores for
receiving the fixing screws.
Figures 2 and 3 also show a wedge-shaped receiving surface 300 for
connection to the driver element 5 which is to be seen in Figure 4. The
wedge-shaped receiving surface 300 is divided into two and has two sliding
surfaces 301, 302, to which respective sliding plates are attached, although
the sliding plates are not to be seen in Figures 2 and 3. The wedge-shaped
receiving surface 300 is at an angle both to the dovetail-shaped portion 30
and also the side with the T-shaped groove 41 for receiving the receiving
means for the processing tool, thus affording an extremely compact
structural shape far the slider element, substantially without unused side
surfaces. That can also be seen in particular from the perspective view of
the assembled wedge drive 1 shown in Figure 4, in which the slider element
receiving means, the slider element, the driver element and the receiving
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13
means for the processing tool are assembled. It can also be seen in that
respect that the driver element and the slider element are connected
together by positively acting return clamps 7. They serve for better
entrainment of the slider element In the rearward strake movement of the
pressing tool. The positively acting return clamps 7 engage both on the
slider element and also the driver element, in openings, recesses or
grooves provided there.
It can be clearly seen from Figure 5 that the positively acting return
1o clamps 7, for that purpose, have protruding portions 70 which can engage
into corresponding grooves in the driver element. It can also be seen from
Figure 5 that sliding plates 303, 304 are fixed on the sliding surfaces 301,
302 by way of fixing screws 305.
The perspective view of the wedge drive 1 in Figure 6, which is
turned through 900 relative to the view in Figure 4, shows a view on to the
receiving means 4 for receiving a processing tool. It will be seen in that
respect that the receiving means 4 is provided with a corresponding wedge
surface comprising two sliding surfaces 43, 44 which can slide on a
corresponding wedge portion 50 of the driver element 5.
It can be even better seen from the side view of the wedge drive 1
shown in Figure 7 that the portion 30 of a dovetail-like configuration, the
wedge-shaped receiving surface 300 and the third side with the T-shaped
groove 41 for receiving the receiving means 4 for the processing tool of the
slider element 3 are respectively arranged at an angle relative to each
other. Each of the sides of the slider element is also at an angle relative to
the vertical or the horizontal respectively which are indicated by
broken lines 8, 9 in Figure 7. Here once again it is possible to clearly see
the extremely compact structural form of the wedge drive.
The corresponding side view in section of the wedge drive 1 shown in
Figure 8 additionally shows a spring element 10 in the form of a gas
pressure spring. It serves to retract the slider element back into its
starting
position in the rearward stroke movement of the pressing tool. That
facilitates the retraction movement of the slider element in the rearward
stroke movement so that a working stroke can be more rapidly performed
again. Depending on the respective configuration of the wedge drive
however it would even be possible to omit such a spring element, in
particular when positively acting return devices of a special design in the
form of the positively acting return clamps 7, for example in the form of
positively acting returning devices with rolling frictional elements, are
provided.
It can also be clearly seen once again from the perspective view on
to the wedge drive 1 of Figure 9 that the slider element is of an extremely
compact configuration by virtue of a suitable arrangement of its three sides
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with a portion of a dovetail-like configuration for engagement into the slider
element receiving means, the T-shaped groove for receiving the receiving
means 4 for the processing tool and the wedge-shaped receiving surface for
co-operation with the driver element 5.
The perspective view of the wedge drive 1 from below with the driver
element 5 removed, as shown in Figure 10, shows that the sliding plates
303, 304 can be of such a length that they also engage under the sliding
surfaces 43, 44 of the wedge surface 42 of the receiving means 4 for the
1 o processing tool, that is to say no further sliding plates are provided
here,
but only the sliding plates 303, 304, so that this arrangement provides a
unitary surface for co-operation with the corresponding wedge portion 50 of
the driver element 5.
The sliding plates 303, 304, with the receiving means for the
processing tool removed, can be seen once again from the perspective view
of the wedge drive 1 from above as shown in Figure 11. It is also evident in
this respect that suitable fixing to the receiving means for the processing
tool is afforded by the provision of a bore 305 in the sliding plates 303, 304
2o and a corresponding fixing screw which however is not shown in Figure 11.
By way thereof, fixing of the receiving means 4 far the processing tool to
the slider element can be still further improved and an even more stable
unit is afforded.
The above-mentioned sliding plates on the slider element and the
driver element as well as the slider element receiving means preferably
comprise bronze with a solid lubricant to permit particularly good sliding
motion of the corresponding pairs of sliding components against each
other. It will be appreciated that in principle it is also possible to use
other
materials far the sliding plates, wherein a low level of friction in the
surfaces which slide against each other means that particularly optimum
movement of the slider element within the wedge drive is possible in the
working stroke and the rearward stroke of the pressing tool in which the
wedge drive is disposed.
Besides the embodiments described hereinbefore and illustrated in
the Figures for wedge drives having a dovetail-like or prism guide means, it
is also possible to form numerous further embodiments in which dovetail shaped
sliding surfaces are provided between the slider element receiving
means and the slider element or prism guides are provided between the
slider element and the driver element and the slider element receiving
means and the slider element. That markedly improves the respective
accuracy of movement of the slider element between the slider element
receiving means and the driver element in comparison with the state of the
art, lateral thrust forces are absorbed and manufacturing tolerances on the
slider element receiving means, the slider element and the guide element
are compensated. The provision of only one dovetail-like or prism guide
CA 02700576 2010-08-23
means between the slider element receiving means and the slider element
makes it possible to save on further components which assist with the
guidance action, and thus manufacture of the wedge drive can be markedly
less expensive than in the state of the art.
5
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16
List of references
1 wedge drive
2 slider element receiving means
3 slider element
4 receiving means for processing tool
5 driver element
6 dovetail-like or prism guide means
l0 7 positively acting return clamp
8 vertical line
9 horizontal line
spring element (gas pressure spring)
portion
15 21 sliding surface
22 sliding surface
23 sliding surface
24 sliding surface
recess
20 26 L-shaped sliding plate
27 L-shaped sliding plate
28 fixing screw
29 fixing screw
portion of dovetail-like configuration
25 31 sliding surface
32 sliding surface
33 sliding surface
34 sliding surface
protruding portion
30 36 sliding plate
37 sliding plate
38 sliding plate
39 sliding plate
T-shaped protrusion
35 41 T-shaped groove
42 wedge surface
43 sliding surface
44 sliding surface
wedge portion
4o 70 protruding portion
300 wedge-shaped receiving surface
301 sliding surface
302 sliding surface
303 sliding surface
45 304 sliding plate
305 bore
