Blade head for cutting blades

A blade head for cutting and planing blades has a blade holder having a plurality of receiving grooves for receiving a cutting and planing blade. The receiving grooves are distributed over the circumference of the blade holder. A plurality of pressurizing elements is positioned in each of the receiving grooves for securing the cutting and planing blade in the receiving groove. At least one adjusting member is positioned in each of the receiving grooves for forcing the pressurizing elements against one another such that the pressurizing elements exert a clamping pressure on the cutting and planing blade. The pressurizing elements have a substantially cylindrical shape with wedge-shaped end faces and a circumferential surface having at least one planar clamping surface. Adjacent ones of the pressurizing elements abut one another with their end faces. The blade holder has clamping counter surfaces cooperating with the planar clamping surfaces of the pressurizing elements.

BACKGROUND OF THE INVENTION 
The present invention relates to a blade head especially for cutting and 
planing blades for wood or plastic machining devices. The blade head has a 
blade holder with a plurality of receiving grooves for receiving a cutting 
and planing blade, the receiving grooves distributed over the 
circumference of the blade holder; a plurality of pressurizing elements 
positioned in each of the receiving grooves for holding the cutting and 
planing blade within the receiving groove; and an adjusting member 
positioned in each of the receiving grooves for forcing the pressurizing 
elements against one another such that the pressurizing elements exert a 
clamping pressure on the cutting and planing blade. 
For clamping blades within a known blade heads, commonly a hydroclamping 
sleeve is used with which via pistons the pressure medium is applied. The 
pressurizing elements for clamping the blades are outwardly forced whereby 
the blade is thus secured within the receiving grooves. A disadvantage of 
these known blade heads is that the clamping pistons within the blade 
holder are radially positioned between the receiving grooves and an 
opening for the spindle of the blade head. This arrangement results in a 
weakened structure of the blade holder within the radial area. 
Furthermore, the blades can become loose when the hydroclamping sleeve or 
one of the clamping pistons has a leak. 
From European publication 0 182 037 a blade head is known in which the 
blades are clamped by steel balls resting at one another within the 
receiving groove. They are forced against one another by an adjusting 
element in the form of a set screw whereby they are alternately forced 
radially outwardly and radially inwardly and rest under prestress at the 
bottom of the receiving groove as well as at the abutment surfaces of the 
blades. With the steel balls only a point contact at the corresponding 
counter clamping surfaces is achieved so that these counter clamping 
surfaces as well as the steel balls are subject to a considerably high 
load and therefore also to great wear. 
It is therefore an object of the present invention to provide a blade head 
of the aforementioned kind with which the blades can be clamped in a 
simple and reliable manner without substantially weakening the blade 
holder whereby a high load on the parts partaking in the clamping process 
should be prevented.

SUMMARY OF THE INVENTION 
The blade head for cutting and planing blades according to present 
invention is primarily characterized by: 
A blade holder having a plurality of receiving means for receiving a 
cutting and planing blade, the receiving means distributed over a 
circumference of the blade holder; 
A plurality of pressurizing elements positioned in each of the receiving 
means for holding the cutting and planing blade in the receiving means; 
At least one adjusting member positioned in each of the receiving means for 
forcing the pressurizing elements against one another such that the 
pressurizing elements exert a clamping pressure on the cutting and planing 
blade; 
The pressurizing elements have a substantially cylindrical shape with 
wedge-shaped end faces, and with a circumferential surface having at least 
one planar clamping surface, with adjacent ones of the pressurizing 
elements abutting one another with the end faces; and 
The blade holder having clamping counter surfaces cooperating with the 
planar clamping surface of the pressurizing elements. 
With the inventive blade head the pressurizing elements with their 
wedge-shaped end faces rest at one another so that an areal force 
transmission can be achieved. Due to the wedge-shaped end faces the 
abutting pressurizing elements are alternately moved inwardly and 
outwardly until they rest with their planar clamping surfaces at the 
counter clamping surfaces provided at the blade head. Accordingly, with 
these clamping surfaces an areal force transmission takes place so that a 
high load of the components participating in the clamping process of the 
inventive blade head is prevented. Furthermore, via the areal support of 
the pressurizing elements at one another and at the counter clamping 
surfaces an optimal force transmission is ensured so that the blades are 
securely clamped within the blade head. During insertion of the blade head 
into a machine a loosening of the blades thus cannot occur. The planar 
clamping surfaces of the pressurizing elements furthermore provide a 
rotational securing means for preventing a rotation of the pressurizing 
elements about their axis. During the clamping process the pressurizing 
elements are aligned relative to one another via their wedge-shaped end 
faces. Via the planar clamping surfaces an alignment relative to the 
counter clamping surfaces takes place so that the areal abutment of the 
planar clamping surfaces at the counter clamping surfaces needed for an 
optimal force transmission is ensured in a simple manner. 
According to a preferred embodiment of the present invention, the planar 
clamping surfaces are positioned at an acute angle to the wedge-shaped end 
faces. Furthermore, each pressurizing element has two of the planar 
clamping surfaces that are parallel to one another. Preferably, a first 
one of the planar clamping surfaces in the axial direction of the 
pressurizing element is shorter than a second one of the planar clamping 
surfaces. 
Advantageously, the receiving means comprises a longitudinal slot into 
which longitudinal slot the pressurizing elements are placed. Preferably, 
the blade head further comprises a clamping member positioned in each one 
of the receiving means, the clamping member being provided with the 
aforementioned longitudinal slot and resting at the cutting and planing 
blade. 
Advantageously, the longitudinal slot has a bottom, longitudinal side 
walls, and an opening opposite the bottom, the opening being narrower than 
the bottom. Preferably, each side wall at the opening has a longitudinal 
projection extending toward one another. Expediently, the distance between 
the projections is greater than a distance between the two planar clamping 
surfaces, and a diameter of the cylindrical shape of the pressurizing 
elements is greater than the distance between the projections. In an 
alternative embodiment of the present invention, the longitudinal slot is 
provided within the blade holder. 
DESCRIPTION OF PREFERRED EMBODIMENTS 
The blade heads according to FIGS. 1 to 10 are primarily used in wood and 
plastic machining devices for planing, profiling etc. When in use, they 
are positioned on a spindle, not represented in the drawings, and are 
rotationally fixedly connected to the spindle. For high feeding speeds and 
high finished surface qualities the blade heads are preferably 
hydraulically clamped at the spindle. 
The blade head according to FIGS. 1 to 3 is provided with a cylindrical 
blade holder 1 which about its circumference is provided with receiving 
means, i.e., receiving grooves 2, spaced at a distance from one another 
for receiving the blades 3. For simplifying the drawings only one of the 
receiving grooves is represented. The grooves 2 have an end view according 
to the representation of FIG. 1 of an approximate trapezoid shape and have 
outwardly converging sidewalls 4 and 5. The bottom which connects the side 
walls has three bottom sections 6, 7, 8. The bottom sections 6 and 8 are 
directly connected perpendicularly to the sidewalls 4 and 5 and are 
connected to one another by a bottom section 7 that extends approximately 
perpendicularly to the section 8. Thus, a step is created by the bottom 
section 7 between bottom sections 6 and 8. The bottom section 8 is 
radially inwardly positioned relative to the bottom section 6. The blade 3 
rests at the longer side wall 5 with its back portion 9 that preferably 
has a non-represented toothing extending approximately parallel to the 
axis. 
The blade 3 is secured in the receiving groove 2 by a clamping unit. The 
clamping unit is comprised of a pressurizing member 10 and a clamping 
member 11 having an approximately rectangular cross-section. The wider 
lateral side of the clamping member 11 is slanted for receiving the blade 
3 and with the planar slanted surface 13 rests at the breast surface 14 of 
the blade The slanted surface 13 extends parallel to the side wall 5 of 
the receiving groove 2. The radially outwardly arranged narrow side 15 of 
the clamping member 11 is provided with a clamping groove 16 (FIG. 11). 
The blade 3 rests with its narrow side 18, that is opposite to the blade 
edge 17, on the bottom section 8, however, it is also possible to provide 
a space between the narrow side 18 and the bottom section 8. With the 
pressurizing member 10 the clamping member 11 is actuated so that the 
blade 3 is clamped within the receiving groove 2. The clamping member 11 
extends preferably substantially over the entire axial length of the blade 
holder 1 and the blade 3 while the pressurizing member 10 may be shorter 
than the clamping member 11 (FIG. 2). 
The pressurizing member 10 is arranged within a U-shaped longitudinal slot 
19 (FIG. 11) provided at the radially inwardly positioned bottom side 12 
of the clamping member 11 that is open to the radially inwardly positioned 
and planar narrow side 12 of the clamping member 11 and delimited by 
sidewalls 20, 21 and the bottom 22 extending in the longitudinal direction 
of the clamping member 11 (FIG. 11). The longitudinal slot 19 is provided 
with radially enlarged portions 23 and 24 at its ends (FIGS. 2, 3) in 
which area the longitudinal slot 19 has a greater depth than in the 
remaining area. The longitudinal slot 19 is delimited on either end by 
sidewalls 19a and 19b of the clamping member 11 (FIG. 2). The sidewalls 
are penetrated by bores 25 and 26 for an abutment 27 and an adjusting 
member 28. The bores 25, 26 extend from the end face 60 of the clamping 
member 11 at a slant in the direction toward the bottom section 6. 
The pressurizing member 10 is comprised of a plurality of pressurizing 
elements 29 to 35, in the shown embodiment seven pressurizing elements are 
provided, which have the same cross-section and the same trapezoidal 
longitudinal section (FIG. 2). The pressurizing elements 29 to 35 are 
arranged to form a pressurizing rod and abut one another, as shown in FIG. 
2. The centrally arranged pressurizing elements 30 to 34 are identically 
embodied. Every other pressurizing element or pressurizing wedge 30, 32, 
34 is arranged in the same manner with their greater base surface 36 to 38 
resting at the bottom 22 of the slot 19. The interposed pressurizing 
wedges 31, 33, when not being clamped, rest with their smaller base 
surface 39 and 40 at the bottom 22. The pressurizing wedges 29 and 35 at 
the end of the pressurizing rod, in contrast to the other pressurizing 
wedges 30 to 34, have asymmetrical long end faces 41 to 44. The outwardly 
arranged lateral surfaces 41 and 44 are shorter than the other end faces 
42 and 43 which are identically embodied to the end faces 45 and 46 of the 
neighboring pressurizing wedges 30 and 34 where they abut. 
The pressurizing member 10 rests with one pressurizing wedge 29 at the 
abutment 27, which in the shown embodiment is a screw. This screw is 
threaded into the threaded bore 25. At the end face 44 of the other 
pressurizing wedge 35 arranged at the other end, an adjusting member 28 is 
provided which is also in the form of a screw. 
For securing the position of the pressurizing members 10, respectively, of 
its pressurizing elements or wedges 29 to 35 within the slot 19 of the 
clamping member 11, a support 47 is provided that is connected to the 
clamping member 11 and is advantageously a holding sheet (FIGS. 1 to 3). 
It is relatively thin and connected with screws 48 and 49 to the clamping 
member, see FIG. 2. 
The pressurizing wedges 29 to 35 are preferably manufactured from round 
stock material so that they are easy to manufacture. However, they can 
also have, for example, a square cross-section. With the supporting sheet 
47 the pressurizing wedges are maintained in their represented positioned 
in which they are abutting one another with their lateral surfaces, 
respectively, their wedge-shaped end faces 42 to 46 and 52 to 59 and, in 
the non-clamped position, rest with their smaller or greater base sides of 
their trapezoidal cross-section at the bottom 22 of the longitudinal slot 
19. In the axial direction the pressurizing wedges are positioned between 
the abutment 27 and the adjusting member 28. The clamping member 11 with 
the pressurizing member 10, the abutment 27, the adjusting member 28, and 
the support 47 may be combined to a premounted unit which as a unit can be 
inserted into the corresponding receiving groove 2 for securing and 
clamping the blade 3. Instead of the pressure or clamping screw used as an 
adjusting member 28, it is also possible to use a spring or a hydraulic or 
pneumatic piston, with which a hydraulic or pneumatic medium is activated, 
for clamping the pressurizing wedges 29 to 35. 
For clamping the blade 3 the pressure or clamping screw 28 is turned in the 
direction of arrow P in FIG. 3 into the bore 26 of the clamping member 11. 
The screw 28 at its free end has a pressure part 61 with which it rests at 
the end face 44 of the pressurizing wedge 35. The axis of the screw 28 and 
of the pressure part 61 are perpendicular to the end face 44. 
When threading the screw 28 into the bore, its pressure part 61 presses 
against the neighboring pressurizing wedge 35 which with its end face 46 
exerts a pushing force onto the neighboring wedge-shaped end face 43 of 
the pressurizing wedge 38. The pushing force has a horizontal and a 
vertical force component. Each pressurizing wedge thus exerts a 
corresponding pushing force onto the neighboring pressurizing wedge 
whereby the pressurizing member 10 is forced against the abutment 27 and 
the centrally arranged pressurizing wedges 30, 32, 34 are forced in the 
direction of arrow P' in FIG. 2 against the clamping member 11. The 
pressurizing wedges 29, 31, 33, 35, on the other hand, are subjected to a 
force in the direction toward the bottom section 6. The support 47 is 
elastically deformed so that it comes into contact with the bottom section 
6 and the pressurizing wedges are able to support themselves via the 
support 47 at the bottom section 6. The clamping member 11 is forced by 
the force acting on it against the blade 3 so that it is fixedly clamped 
within the receiving groove 2 between the slanted surface 13 of the 
clamping member and the neighboring sidewall 5 of the receiving groove and 
is thus securely fastened in this position within the groove. This 
clamping method is especially useful for very long blades 3 for clamping 
them securely over the entire length. Since the pressurizing member 10 is 
comprised of individual pressurizing elements provided with edge-shaped 
end faces which, compared to the length of the clamping member 11, are 
short it is not necessary to manufacture the pressurizing elements 29 to 
35 exactly to the dimensions of the clamping member 11. Every other 
pressurizing element is firmly pressed against the bottom 22 of the slot 
19 of the clamping member 11 due to the aforedescribed embodiment. 
In order for the pressurizing wedges 29 to 35 to be axially and 
circumferentially exactly aligned with one another they are provided with 
securing elements that prevent their rotation relative to one another. 
Thus, it is ensured that the pressurizing wedges 29 to 35 with their 
respective wedge-shaped end faces 42, 45; 52, 58; 54, 55; 56, 57; 58, 59; 
43, 46 rest areally at one another. The clamping force generated with the 
screw 28, as described above, is thus maintained during machining 
processes performed with the blade head. 
The securing elements are in the form of planar lateral surfaces 75 and 76 
(FIG. 18) at the pressurizing elements 29 to 35 with which they rest at 
the corresponding counter clamping surfaces during clamping. In FIG. 11 
this is represented for the pressurizing wedges 33 and 32. They are, as 
explained above, forced against the (non-represented) support 47, 
respectively, against the bottom 22, as can be seen in FIG. 11. 
As can be further taken from FIG. 11, the support 47 must not be provided. 
It may be advantageous to clamp the corresponding pressurizing wedges 
directly against the bottom section 6 of FIG. 1 of the receiving groove 2. 
In the clamping position the pressurizing wedges rest with their lateral 
surfaces 75, 76 areally at the corresponding counter clamping surfaces. It 
is thus ensured that the pressurizing wedges 29 to 35 are exactly aligned 
so that the force generated by the screw 28 is transmitted via the 
wedge-shaped end faces onto the pressurizing wedges 29 to 35 in a reliable 
manner. 
The distance of the lateral surfaces 75, 76 of each pressurizing wedge 29 
to 35 is slightly smaller than the distance between the projections 77, 78 
which are extending toward one another (FIG. 11) and project past the 
sidewalls 20, 21 of the longitudinal slot 19. Thus are arranged at the 
level of the underside 12 of the clamping member 11. The pressurizing 
wedges 29 to 35 are inserted into the longitudinal slot 19 such that their 
lateral surfaces 75, 76 are oriented parallel to the ends of the 
projection 77, 78. Subsequently, they are rotated about their longitudinal 
axis about 90.degree. within the longitudinal slot 19 to be positioned as 
required for their correct mounting. In this position, the pressurizing 
wedges 29 to 35 can no longer fall out of the longitudinal slot 19 due to 
the projections 77, 78. Due to these projections 77, 78 a support 47 is no 
longer needed. The corresponding pressurizing wedges in the clamping 
position project past the projections 77, 78 from the longitudinal slot 19 
and are supported with their corresponding lateral surfaces 75, 76 at the 
bottom section 6 of the receiving groove 2, as is clearly shown in FIG. 11 
with the exemplary pressurizing wedge 33. 
The longitudinal slot 19 within the clamping member 11 is deep enough so 
that the pressurizing wedges 29 to 35 can be clamped with a required force 
at the bottom 22 and at the bottom section 6. 
The wedge angle .alpha. (FIG. 12) of the pressurizing wedges 29 to 35 is 
preferably 45.degree. and in any case is smaller than the angle with which 
self-hindrance would occur. During the clamping process the pressurizing 
wedges can therefore be easily displaced relative to one another. Since 
the pressurizing wedges are contacting one another in an areal manner and 
rest with their lateral surfaces 75, 76 areally at the counter clamping 
surfaces, an optimal force transmission with minimal wear is ensured. 
The embodiment according to FIG. 4 differs from the aforedescribed 
embodiment essentially by providing the pressurizing member 10' in a 
longitudinal slot 19' of the blade holder 1' at the bottom of the 
receiving groove 2'. The longitudinal slot 19' is substantially 
identically embodied as the longitudinal slot 19 according to the 
embodiment of FIG. 1 to 3 and provided as a depression within the bottom 
section 6' of the receiving groove. The longitudinal slot 19' is 
symmetrically arranged relative to the receiving groove 2' and is 
outwardly closed by a support 47' that is connected with its longitudinal 
edges to the bottom section 6' and secures the pressurizing wedges 
arranged within the longitudinal slot 19'. When the clamping member 11' is 
provided with projections 77, 78 according to FIG. 11, the support 47' is 
not necessary. The clamping member 11', with the exception that the 
longitudinal groove 19 is missing, is embodied identically to the clamping 
member 11 of FIGS. 1 to 3. The pressurizing member 10' is embodied 
identically to the pressurizing member 10 of the aforedescribed 
embodiment. The longitudinal slot 19' on both ends is closed off by the 
end faces of the blade head 1' in which the abutment and the adjusting 
member are supported in the same manner as in the embodiment described 
supra. They are arranged in a recessed manner so that they do not project 
outwardly in the axial direction. When threading the adjusting member, not 
represented in the drawing, into the bore, the centrally arranged 
pressurizing wedges of the pressurizing member 10' exert in the 
aforedescribed manner radially outwardly oriented pressure forces on the 
clamping member 11' while the interposed pressurizing wedges are forced 
radially inwardly against the bottom 22' of the longitudinal slot 19'. The 
support 47' is elastically deformed and rests at the planar underside 12' 
of the clamping member 11'. Accordingly, the clamping member 11' is loaded 
in the aforedescribed manner by the pressurizing wedges in the direction 
of arrow P' so that the blade 3' is clamped between the slanted surface 
13' and the side wall 5' of the receiving groove 2'. 
The embodiment according to FIG. 5 differs from the embodiment according to 
FIG. 4 only by having the longitudinal slot 19" for receiving the 
pressurizing member 10" arranged in the sidewall 4" of the receiving 
groove 2". The pressurizing wedges of the pressurizing member 10" contact 
via the support 47" the clamping member 11" on a side thereof oppositely 
arranged to the blade 3". The pressurizing member 10", the clamping member 
11", and the receiving groove 2" are otherwise identically embodied as in 
the aforedescribed embodiments. During clamping the clamping member 11" is 
forced by the pressurizing wedges of the pressurizing member 10" in the 
aforedescribed manner against the blade 3" which is thus securely clamped 
within the receiving groove 2". When the longitudinal slot 19" is provided 
with projections 77, 78 according to FIG. 11 the support 47" is not 
required. 
In FIG. 6 a further embodiment is represented in which for clamping of the 
blade 3"' within the receiving groove 2"' of the blade holder 1"' only the 
pressurizing member 10"' is provided which is arranged in the longitudinal 
slot 19"' of the blade holder. In this embodiment a clamping member is not 
necessary. The longitudinal slot 19"' is a depression in the side wall 4"' 
of the receiving groove 2"' and extends parallel to the axis. The 
non-represented pressurizing wedges of the pressurizing member 10"' are 
secured within the longitudinal slot 19"' by the support 47"' which is 
attached, as disclosed in the embodiment according to FIG. 5, with its 
longitudinal edges within flat depressions directly adjacent to the slot 
19"' within the side wall 4"' of the receiving groove 2"'. The blade 3"' 
to be clamped can thus rest directly at the flat depressions within the 
side wall 4"'. The longitudinal slot 19"', as described supra, is closed 
by the end faces of the blade holder 1"' The pressurizing wedges rest at 
the non-represented abutment and the non-represented adjusting member 
which are arranged within the end faces of the blade holder 1"' in a 
recessed manner. In this embodiment the pressurizing wedges of the 
pressurizing member 10"' act directly via the support 47"' on the blade 
3"'. The clamping groove 16"' is arranged in front of the blade 3"' within 
the blade holder 1"' and extends forwardly in the direction of rotation in 
the circumferential direction from the sidewall 4"', of the blade holder 
1"'. 
The supports 47, 47', 47", 47"' have the same function as the projection 
77, 78, i.e., to secure the pressurizing wedges against falling out of the 
corresponding longitudinal slots 19, 19', 19", 19"'. When projections 77, 
78 are provided they take over the securing function so that the supports 
47 to 47"' are no longer required. The securing elements or supports 
further prevent that dirt can be introduced into the longitudinal slots 
and soil the pressurizing wedges thereby inhibiting the easy 
displacability of the wedges. 
In the embodiment according to FIGS. 1 to 6 the pressurizing members of 
each individual blade are actuated individually, as has been described for 
the embodiments according to FIGS. 1 to 3. 
However, it is also possible that all pressurizing members are actuated by 
one clamping device simultaneously. Two of such embodiments are shown in 
FIGS. 7, 8 and 9, 10. 
In the embodiment according to FIGS. 7 and 8 one single adjusting member 63 
is provided instead of the individual pressure and clamping screws 28 
coordinated with each individual pressurizing member. The adjusting member 
63 is in the form of an adjusting ring which is positioned on the spindle 
64 of the blade holder and which can be attached and secured to it. At the 
underside 66 facing the end face 65 of the blade holder 1a the adjusting 
ring is provided with a zigzag profiling shown in a side view in FIG. 8. 
Upon rotation of the adjusting ring 63 the zigzag profiling cooperates 
with the pressurizing parts 10a and 10d. The pressurizing members are 
essentially identically embodied to the pressurizing member 10 of FIGS. 1 
to 3. They differ only in that the pressurizing elements 35a and 35d 
arranged at the ends extend past the end face 65 of the blade holder 1. 
The projecting ends with the end faces 67 and 68 cooperate with the 
underside 66, respectively, the profiling of the adjusting ring 63 at 
which they are areally supported. In the represented clamping position of 
the pressurizing parts 10a and 10d the end faces 67 and 68 of the 
pressurizing members are positioned within the area of the projection 69 
to 71 of the underside 66, while before clamping the blades 3 within the 
receiving groove 2 of the blade holder 1 they are positioned within the 
area of the depressions 72 to 73 of the adjusting ring 63. The profiling 
66 is embodied such that upon rotation of the adjusting ring 63 the 
pressurizing wedges of all pressurizing members 10a and 10d are 
simultaneously pressed against one another so that in the aforedescribed 
manner the blade 3a is clamped within the receiving groove 2a. At the end 
opposite the adjusting ring 63 an abutment is provided that is identical 
to the one disclosed in FIG. 2. 
In the embodiment according to FIGS. 9 and 10 the adjusting member 63' is 
again in the form of an adjusting ring with which all pressurizing members 
10a' can be simultaneously adjusted for clamping the knives 3a'. The 
adjusting ring 63' differs from the adjusting ring 63 according to FIGS. 7 
and 8 by having the underside 66' as a planar annular surface. The 
pressurizing elements 35a' rest with their end faces 67' at this annular 
surface. The adjusting ring 63' is provided with an inner thread with 
which it is threaded onto the outer threaded portion 74 of the spindle 
64'. With the adjusting ring 63' all blades 3a' of the blade head can be 
clamped simultaneously via the pressurizing members 10a' and the clamping 
members 11a', as described for the embodiment of FIGS. 7 and 8. For this 
purpose, the adjusting ring 63' is threaded onto the spindle 64' in the 
direction toward the blade head 1a' so that the pressurizing wedges of all 
pressurizing members 10a' are simultaneously pressed against one another, 
thereby clamping the blades 3a'. 
Of course, it is also possible to use instead of the mechanical adjusting 
members 63 and other adjusting devices for simultaneously clamping the 
blades. For example, the pressurizing elements can also be simultaneously 
activated by hydraulic, pneumatic or other adjusting members. In each 
case, however, it is also possible to individually clamp the blades with 
the clamping and pressurizing members, as described in the embodiment 
according to FIG. 6, with the pressurizing members within the blade head. 
In the embodiments according to FIGS. 7 to 10 the clamping devices can also 
be embodied as disclosed for the embodiments of FIGS. 4 to 6. 
The present invention is, of course, in no way restricted to the specific 
disclosure of the specification and drawings, but also encompasses any 
modifications within the scope of the appended claims.