CA1195215A - Composite reducer head assembly - Google Patents

Abstract

ABSTRACT

A composite reducer head assembly with a reducer head having a peripheral part and a central part is at the central part provided with at least one addi-tional operative means , which may be a guide means or a machining means, and which is adapted to affect a piece of timber machined by the peri-pheral part in a different rotational and/or positional mode than the peripheral part. Side guide means displace-able in dependence of possible axial displacements of the additional means may be provided at one or two downstream levels.

Description

The invention relates to a composite reducer head assel~ly for timber working machines, comprising a reducer head having a peripheral part in the general shape of a trun-cated cone and encompassing by its circular inner edge a central part with a generally disc-shaped front face. The peripheral part is supported and driven in rotation by a first shaft means and at least one wood chipping means such as knife or similar is provided thereon. At least one additional operative MeanS for affec-tiny a processed piece of tim~er at a dif~erent rotational speed than the peri~
pheral part is arranged on the central part, and at least one second shaft means is provided to support said addi-tional means. Reducer heads operate generally as a pair in coaxial arrangernent in timber processing machines and a pair of reducer heads of the kind aforesaid is shown and described ln U.S. patent 3,812,891 issued on May 28, 197~, to Alfred Reu-ter. In this embodimen-t, the centr-al part is along its periphery provided wi.th a plurality of , finishing blades arranged in a ring or as radially extending saw -teeth, both the said ring and the said teeth being concentric with peripheral and cen-tral parts of the re-ducer head. The cen-tral part rotates always at a higher speed than the peripheral part.
~, ~

~ 2 ~3~5 .

The present inven-tion provides an improved composite re-ducer head assembly enabling to apply more varied modes of working and/or providing improved sidewise yuiding fa-cilities of timber trunks passing through a processing machines. The characterizing features of the present in-vention are evident from the attached patent claims.
According to the invention, there is essentially provided a reducer head having in the central part or portion mounted at least one additional operative means, which can be a machining means or a guide means, and which is kinematically independent of the peripheral part or por-tion of the reducer head in the sense of as well the speed as the direction of rotation, and also the axial position. The additional means can no-t only rotate at a higher speed, as has already been proposed, but also at a lower speed~or it can remain stationary when the peri-pheral part ro-tatesO In different embodiments which will be described later in greater detail, -the addi-tional ope-rative means may be flush with the inner edge of the periphe-ral part or it may project therefrom -to a selec-ted degree,it may rotate about an axis different from the rotational axis of the peripheral part or portion or even as well to ro-tate about its own axis, as to move along a circular patharound the axis of the peripheral portion.

3 ;:~9~

The invention will now be described more in detail with reference to the accompanying schematic drawings which show exemplary embodiments and in which:

FIG. 1 is a plan view, partly in section, of a first embodiment of the invention;
FIGS. 2 ~ show in plan view, partly in section, a second and 3 J and a third embodiment;
FIGS. 4a ~ illustrate linearly movable planar guiding and 4b J members applicable in assemblies according to FIGS. 2 or 3;
FIGS. 5 l illustrate four further embodiments of the pre-to 7 J sent invention;FIGS. 8 illustrate in side elevation and in plan view and 9, respectively three other embodiment~ of the 10 and 11, invention.
12 and 13 Referring now to the drawings, wherein identical reference characters are used -to refer to parts wi-th essentially identical shape and function, there is shown in FIG. 1 one side of a machine for reducing (side processing) a piece of timber 10 having a centre line CL and forwarcled on a conveyor 101 (which for simplici-ty will not be repeated in subsequent plan view drawings) in the di.rection of `.

4 ~ ~S ~ ~

arrow A~so that a block 10' having planar side faces 1OA
is obtainedD The other side of the m chine is identlcal as shown in FIGS. 4a and 4b. A reducer head 11A has a peripheral portion, in the example shown defined by a separate peripheral part 110, encompassing or surrounding by its inner edge 111B a central portion~in the instance also defined by a separate part 120. Peripheral part 110 has generally the shape of a truncated cone (possibly with steps, as in the embodiment shown) limited by said inner edge 111B and by an outer edge 111C, and is provided with a plurality of wood chipping means such as straight blades 11la. Inner edge 111B limits a circular centre front portion wherefrom a cylindrical space M extends into the body of reducer head. In said space M is a separate centre part 120, having a planar front face 121 and a cylindrical sid~ face 122, situated. The peripheral part 110 is mounted on a hollow, tubulax shaft 12 defining first shaft means, and the central part 120 is mounted on a massive shaft 13 defining second shaft means and located and guided in the hollow of tubulax shaft 12. Shaft 12 is via gears 14a, 14b operatively connected to an electric motor 16 and is axially displaceable in the sense of arrow C, e.g. together with motor 16, for adjustment of the spacement N (FIG.4a) to an opposite reducer head, so that timber trunks with varying diameters can be processed.
Alternatively, at least one of the gears 14a, 14b may be sufficiently broad as to allow such setting motion with a stationary motor 16. Such axial setting of a reducer head is known.

5 ~:~L95~
.

Central part 120 has the shape o~ a low ~i.e. with greater diameter than height3 cylindrical body which is either on its planar ront face 121, or on its cylindri-cal side face 122, or on both (as illustrated in FIG. 1), provided with additional operative means, in the example shown with additional working or machining means defined by cutting or chipping elements (spikes~ 121a, 122a. The peripheral and central parts rotate about a common axis D, but generally at different speeds and/or in different axial positions.

Shaft 13 is driven by another electric motor 15 slidably mounted in a rectilinear guide 201, parallel with shaft 13. A double-working cylinder-piston-unit 200, fed via pipes 202 and a command (distributor) valve 203 with pressure fluid supplied through pipe 204 from a pressure fluid source (not shown) is arranged to move motor 15, shaft 13 and central part 120 in both senses of arrow B, independently on possible displacements of shaft 12 in the senses of arrow C. Valve 203 is by an electric line 100a connected to a dator type electronic unit 100, shown in FIG. 2.

Alternatively, the additional operative means may be a guiding means without any machining function, such as, e.g. accoxding to FIG. 2, a smooth front face 121A on centre part 120A, which part then has machining means only on the side face 122'. Such centre part carries thus operative means of two different kinds affecting a piece of timber processed by the peripheral part, viz.
a machining means and a guide means.

The reducer head llB of Fig. 2 has a separate 5. centre part 120A with a side face 122' which in its outer portion tapers outwardly and which is provided with wood chipping and cutting elements, defined by straight edges 122a, on the cy:Lindrical as well as on the tapered portion.
Central par-t 120A may be selectively moved out, e.g. as far as into the position 120' shown in phantom, where it lies closer to the centre line CL of trunk 10 than inner edge lllB. Peripheral part 110 is in the side and bottom walls of space M provided wi-th openings 112 for discharging chips produced by the elements 112a. Shafts 12 and 13 are driven each by its own tor 15, 16 via a belt drive 15A and 16A respectivelyr allowing independent displacement of both shafts in bo-th senses of the arrows B, C even if motors 15, 16 are stationarily mounted. Belt drive 15A includes belt discs 13B, 15B and belt drive 16A
includes belt discs 12B, 16B. The front face 121A of centre part 120A is smoo-th and defines a guide means.

Reducer head llB belongs, together wi.th an opposite ~., ,~, ' 7 ~ ~

reducer head of the same kind, not shown, to a timber working or processing machine where downstream the two heads at least two saw blades such as blade 18 are pro-vided. Downstream each reducer head 11B and upstream each saw blade 18 there is provided a side guide means 17 overbridging the distance between the reducer heads and the saw blades. According to the invention, the side guide means 17 is pivotally mounted on a vertical pi~ot pin 17a which is anchored in part 17b rigidly connected to the mount 12a of shaft 12. Mount 12a is displaceable in the sense of arrow C for said setting of spacement N.
Consequently, part 12b follows this setting movement of the peripheral part 110, carried out before processing of any trunk 10 is begun.
Side guide means 17 can pivot in both senses of arrow B' in order to follow centre part 120A, e.g. to the posi-tion 17' and back. Thus guide means 17 follows on the one hand, in conventional manner, the setting movement of the peripheral part 110 Clinear motio~, and, in a novel manner, also the axial displacement of the central part 120A (pivotal motion)~ In the example shown, side guide means 17 is defined by a planar plate having a tapering leading edge 17C and carrying at its downstream end a rotary roller 17D the periphery of which is sub-stantially tangential to the face of the planar plate which is closest to the centre line CL of the processed trunk.

8 ~9s~s A double-working cylinder-piston-unit 170 is pivvtally mounted on part 17B and the projecting piston rod 171 thereof i5 pivotally attached to the side guide means 17 spacedly from pin 1ia. Unit 170 is supplied with pressure fluid from a command (distributor) valve 173 and through flexible hoses 172. Pressure fluid is supp-lied to valve 173 from a source (not shown) via a pipe 174.

19 Distributor valve 175 is by an electric line 100b con-nected to a programmable, computor type electronic unit 100 from which also a plurality of other electric lines 100a lead to other controllable parts of the assembly, such as to command valve 203 of FIG. 1.

Unit 170 is arranged to swing out the downstream end of side guide means 17 and to retract it to the same degree as shaft 13 can be moved out and withdrawn. Dator unit 100 is programmed ts send command siynals to the distri-butor valve 173 either simultaneously with command sig-nals to operating means for displacement of the respec-tive reducer head's centre part (distributor valve 203), or with a selected delay. When the centre part is being retracted ~i.e. when it passes from position 120A' to position 120A), the delay is selected so that piston rod 171 is retracted first when step 10' on the log 10 has reached the upstream edge 17c of the side guide means 17 .

Step 10' was created when centre part 120A has left its projecting position, and with known -transport speed of 9 ~ s trunk 10 on conveyor 101 said delay may readily be ascer~
tained.

When the centre part is stepped out, e.g. into position 120A', in order to receive the na.rrow top end of a new log, piston rod 171 is retracted only after the wide root end of a preceding log has left the roller 17D.

In FIG. 4a is shown side guide means 270 defined by a planar guide plate which can be displaced rectilinQarly, i.e. parallel with itself, but otherwise in the same mode as guide mean~ 17, i.e. either simultaneously, or with a delay, relative to the centre part. Means 270 is rigidly attached to the piston rod 271A of a steadily anchored cylinder-piston-unit 271 and is supplied with a pressure medium in the same way as shown in FIG. 2. It will be observed that the timber processing machine comprises a pair o~ co-axial reducer heads 11~, a pair of opposite guide means 270 and two saw blades defined by band saw blades 18' running over wheels 318. The centre parts 120A of the reducer heads have a smooth front face 121 which, with the exception of said possible delays, is flush with the side guide means 270, and the cylindrical side faces of the centre parts are provided with machining spikes 122a. According to FIG. 4b, two pairs of side guide means 270, 272 are provided, each activated by its own cylinder-piston-unit5271, 273 controlled by dator comman-ded distributor valves, as shown in FIG. 2.

~5~5 In Fig. ~b is illustrated -the situation shortly after the centre parts 120A have been retracted to the zero position, shown in the drawing, after having been for some time stepped out -to a position flush with the illustrated position of side guide means 272. When the centre parts 120A have occupied their moved out position, also guide means 270 of the other pair were in the position now illustrated with guide means 272. Guide means 270 have not been re-tracted simultaneously with -the centre parts 120A, but somewhat later, viz. when the steps 10' have reached the downstream ends of the centre parts 120A.
Guide means 272 will now shortly follow in this retractive movement to allow steps 10' to enter between them. At known transport speed of timber trunk 10 in the sense of arrow _, the necessary delays can be readily calculated and the dator unit 100 accordingly programmed. It will be noted that trunk 10 is continuously rigidly guided side-wise in all processing steps until i-t reaches the saw blade section.
In the following drawings, Figs. 3 and 5 to 13 will be illustra-ted embodiments where the at least one additional operative means is kinematically separated from the centre portion or centre part.

In Fig. 3 is shown a por-tion of a similar process-ing machine with saw blades 18 and side guide means 17.
Reducer head llC has, in contras-t to -the previously des-cribed embodimen-ts, a central portion 120' which in conven-tional manner is integral with the peripheral portion 110' and thus supported and driven by the same first shaft means 12' and the same motor 16 (via a bel-t transmission 16A) as the peripheral por-tion 110'. Part 17b carrying the pivot pin 17a is in this embodiment displaced in accor-.

~ ~ ~

., 52~5 ?

dance with the displacements of the shaft 12' which is also conventional and is not illustrated in detail in the drawing. In a novel manner, however, at least one addi-tional operative means, in the instance a pair of coun-ter-rotating cylindrical cutters 20, is mounted in the centre portion for rotation together therewi-th and, more-over, about their own a~es Each cutter 20 has the shape of a sharply cut-off drill with helical grooves 20a for chips and is affixed to the first end of a shaft 21, de fining said second shaft means with an axis I. Shafts 21 are mounted for rotation and for linear displacement in both senses of arrow B in centre portion 120' and to their projec-ting other endS are gears 22 affiXed-To shaft 12l/ which freely passes through a sleeve or tube 219, is a larger gear 220, meshing with both gears 22l affixed. Gears 22 and 220 define together a planetar gearing. At leastei-ther the meshing gears 22 or the meshing gear 220 have sufficient dimension in axial direction to allow relative displacement in the sense of arrow B without interrupting the transfer of -torque. In the drawing are the gears 22 shown to be broader to this purpose. Sleeve 219 can either be mounted stationarily, or it may define a hollow shaft of an elect-ric motor 15' and can then rotate at different speed and/or in reverse sense than shaft 12'.

When sleeve 219 is moun-ted stationarily, the cutters 20 ; are rotated with a speed depending on the selected ratio between the diameters of the gears 22 and 220. When sleeve 219 is driven by a separate motor, the ro-tational speed of :

.

12 ~ ~ 95~

the cutters 20 is quite independent o the rotational speed of the peripheral portion 110'.

Shafts 21 have end portions 21b which slightly project beyond the gears 22 and rest on a non-rotary catch plate 23 towards which they are constantly pressed by helical springs 21a slipped on the shats 21 between the gears 22 and an opposite face of reducer head 11C. Catch plate 23 may either be rectilinearly displaced in the sense of arrows B'', or it may be arranged to rock about a trans-verse axis 23A, e.g. to the position 23' shown in phantom.

In the first named case, all cutters 20 are stepped out and withdrawn at the same time and to the same extent.
In the last named case, rocking of plate 23 induces a reciprocating motion of the cutters 20 as they rotate about the axis D of shaft 12'. It will be noted that catcher plate 23 may be constantly rocked to this pur-pose, but that it also is sufficient when plate 23 is stationarily kept in a position not at right angles to axis D. In practice, a shaft 21 may preferably be defined by a cone or a shaft of a quick-grip-head, carrying gear 22. Lt will be readily understood that also a diferent number of cutters 20 may be used.

In dependence of the selected mode of driving gear 220 (stationary, greater or smaller speed than shaft 12'),the additional machining means provided, such as cutters 20, process trunk 10 at a different rota-tional speed than ~, peripheral portion 110' inclusi~e at considerably highex speed.

In FIG. 5 is shown a centre part with an additional ope-rative means having exclusively guiding function (in con-trast e.g. to centre part of FIG. 2 with machlning and guiding operative means3. A reducer head 1lD has a free space M occupying practically the entire centre portion thereof, also in axial direction. A centre part defining a carrier means, e.g~ in the form of a massive cylindri-cal body 19,is arranged in space M. The rear end 19a of body 19 projects from the rear end 12' of shaft 12 in the same way as e.g. shaft 13 does in FIG. 2, and shaft 12 is also in the same way as in FIG.2 at its rear end ~rov.ided with.a belt disc 12B t ~ r~ edJ or possibly with a gear 14a as in FIG. 1. The projecting reax end 19a is non-rotarily, but displaceably in the sense of a.rrow B, mounted in a stationary part H of the assembly or process-ing rnachine. In the front portion 19b of carrier 19 is a smooth, freely rotatable cylindric roller ?4 mounted on a shaft 24A. Shaft 24A defines said second shaft means and has an axis P which extends at right angles as well to axis B, as to transport direction A, in other words perpendicularly to the plane of conveyor 101, i.e.
to the drawing plane of FIGS. 1 to 4 li.f the device would be used in connection with the assemblies illust-rated therein)~ Roller 24 defines an additional operative means which is a guide means with superior performance than a simple smooth front face 121.

S

At the inner edge 111B of peripheral part 110 is a sub-s-tantially planar, annular zone 11OA arranged in which machining elements 113 are mounted which may be of the same type as the eiements provided on the peripheral pa-rt 110 , or of a different type. Means 113 are no-t additio-nal operative means, as herebefore defined, because they are no-t independent of the peripheral part. Openings 113A are provided fort the discharge of chips.

In FIG. 6 is shown an al-ternative emhodiment of the front portion l9b' of a carrier 19. All the remaining parts are substantially the same as in FIG. 5 and are not repeated for simplicity. The same applies also to subsequent FIG. 7.
The embodiment of FIG. 6 differs from the embodimen-t of FTG. 5 principally in two aspects. Smooth guiding roller 24 has been replaced by a machining roller 24b, and thus is driven by a motor, not shown, via a belt 124 and a belt disc 124a affixed to a shaft 24A', defining said second shaft means, and to which also roller 24b is firmly affixed.
Shaft 24A' is ro-tarily mounted in front portion 19b'~
The surface of roller 24b may have selected quality, such as being an abbrasive, or a cu-t-ter, e.g. analogous to cutter 20 of I~'IG. 3, as illustrated, etc.

An embodiment defining a more complex machining device, rotarily mounted in front por-tion 19b" of carrier 19, is illustrated in FIG. 7. Shaf-t 24~', belt disc 124a ,, 1 5 ~L~L95~l5 non-rotarily mounted on shaft 24A', and driving belt 124 are the same as in FIG. 6. Two disc-shaped milling cut-ters 25A, 25B with cut~iny side faces 25AI, 25B' are s~acedly mounted on shaft 24A' and a circular saw blade 5 ~ 2~ is mounted on shaft 24A' between the cutters. A trunk 10, transported on conveyor 101,has planar side faces 10A machined by the peripheral part o the respective reducer head 11D. Into these side faces are now notches or cuts made in dependence on the character of the addi-tional machining means mounted on shaft 24A'. So cane.g. wane~ ~dull edges) on a future plank (separated from the trunk by saw blades 18 or 18', FIG. 1-4) be removed immediately in the reducer part of the process-ing machine, as in the case of the illustrated example.
With the interrupted double line 18" is shown the kerf which in log 10 will be made by saw blade 18 or 18' when the cross-section of the log illustrated in FIG. 7 reaches the saw blade. Thanks to the preparatory work done by the cutters 25A, 25B and also by the saw blade ~9 ~, two fully machined tirnber pieces 1Ob and 10c will then automatically be obtained. The cross-sectional di-mensions of these pieces can be selected by appropriate dimensioning of the means 25A, 25B and 26 and their ~ q setting on shaft 24A'. Saw blade.~ has a somewhat smaller diameter than -the cutters 25A, 25B in order that no trace be left at 18"a; the difference may amount e.g. to half the width of kerf 18'l.

It will be understood that in the embodiments of FIGS.

6 and 7 the belt drive 12~, 124a also can be replaced by a driving shaft parallel with axis D and a bevel gear drive. While it is not necessary for carrier 19 in the embodiment of FIG. 6 to be mounted non-rotarily, non-ro-tary mounting is mandatory in the embodiment of FIG. 7.
Carrier 19 may, however, in the embodiment of FIG. 7 preferably ~e smaller in the direction of shaft 24A' than what the diameter of the space M (FIG. 5) is, thereby allowing a setting Irelative to the plane of con-veyor 101~ also in the sense of arrow V, additionally tothe setting in the sense of arrow B.

In FIGS. 8 and 9 is illustrated a reducer head 11D simi-lar to that of FIG. 5, in the central space M of which a centre part defined by a cylindrical carrier 120B, similar to carrier 19 of FIG. 5, but hollow, is accomo-dated. Carrier 120B has a frcnt face 120B' and the arrangement of the rear portion of the assembly is the same as shown in FIG. 5 or FIG. 13.

An additional machining means 26, e.g. a cutter of the same sort as cutters 20 cf FIG. 3, has a shaft 13 de-e~c e ~
fining said second shaft means, ancLwhich is~l~unted in an opening in the front face 120B'. Cutter 26 is driven by a motor of its own (not shown). Carrier 120 is/likewise ' as carrier 19, not driven in rotation, but it can be ro-Il tated in the senses of arrow G in its mount ~ (FIGS. 5 and 13) for setting purposes. For this setting~carrier 120B can be provided with a gear similar to gear 14a, ~' 17 3 ~L 952~5 and meshing with a hand operated gear similar to gear 14b, or with a hand operated gear rack. By such setting, the posltion of means 26 rel~tive to the trunk 10 is ad-justed, more precisely the vertical distance h between the axes D of the reducer head and I of the additional means is set. Head 1lD rotates in the sense of arrow E
and means 26 rotates in the sense of arrow F. Means 26 can be, together with its shaft 13, displaced ~n the senses of arrow B relative to the carrier or centre part 120B, which in its turn is not axially displaceable rela-tive to the peripheral part 110" of head 11D. Side guide means 270' is mounted in the same way as part 17b in FIG. 2, i.e. for rectilinear common displacement with the peripheral part 110, because a portion 1OA' of the planar side face 1OA of trunk 10, produced by the peri-pheral part 110, always remains unaffected by the addi-tional working means 26. There is therefore no need for guide 270' to follow cutter 26 in the projecting posi-tion.
In the embodiment of FIGS. 10 and 11 there are two cut-ters 26A, 26B provided, similarily to FIG. 3, and they are adjustable in their position by a rotational setting movement of centre part 120C tangle ~). Centre part 120C
with front face 120C' differs from centre parts 19 and 120B by not being a cylindrical body, but a circular plate supported by a rod 123, rotarily mounted (for set-ting purposes) in mount K. Cutters 26A, 26B are driven by a motor other than by which shaft 12 is driven, possibly with the aid of a planetary gear as shown in FI~. 3. The axis or axes I in the embodiments of FIGS~ 3, 8 and 10 orbit round the axis D of the peripheral part or por-tion.

s Accoxding to FIGS. 12 and 13, the additional working means is defined by a cleaving circular saw blade 27 mounted on shaft t3 which in its turn is rotarily mounted in the separate centre part 12OB, in the same way as shown in FIG. 9. The rear end 120B" of carrier or centre part 120B, projecting from the rear end 12' of tubular shaft 12, is rotarily mounted in a mount ~for setting purposes. The rear end 13' of shaft 13 pro~ects from the rear end 120B" of centre part 120B and is provided with a drive means such as e.g. a belt disc 13B, driven via a belt 15A by a motor other than by which shaft 12 is driven~

By adjusting setting angle ~, a convenient distance 1 of the axis I of the saw blade 27 downstream from the axis E of the reducer head 11D is adjusted in this em--bodiment, because a cleaving operation shall not take place too much forwards.The concurrently occuring change of the vertical distance _ (FIG. 8) between the two said axes is rather lrrelevant with a saw blade.

., .

Claims (15)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN
EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:

1. A composite reducer head assembly for timber work-ing machines, comprising a reducer head having a peripheral portion in the gene-ral shape of a truncated cone with an inner edge (111B) surrounding a central front portion ; first shaft means to support and drive in rotation said peripheral portion; at least one wood chipping means provided on said peripheral portion to process a trunk of timber having a centre line and transported on a conveyor past the rotating peripheral portion; at least one additional operative means situated in said central portion for affecting said trunk at a different rotational speed than the peripheral portion; and at least one second shaft means for supporting said addi-tional means, wherein said at least one additional means is mounted for affecting said trunk in at least one of the following modes: closer to said centre line than said inner edge, rotating in reverse direction and/or at a lower speed, including zero speed, than the peri-pheral portion, rotating about a different axis than the peripheral portion, inclusive an axis perpen-dicular to and an axis orbiting round the axis of the peripheral portion.

2. The assembly of claim 1, wherein said at least one additional operative means is kinematically separated from said centre front portion.

3. The assembly of claim 2 with a reducer head having a centre front portion integral with and supported and driven by the same first shaft means as the peripheral portion, wherein said at least one addi-tional operative means is a machining means which with the aid of said at least one second shaft means is rotarily mounted in said centre portion and so that it can occupy a closer position to said centre line than the centre portion.

4. The assembly of claim 3, wherein said at least one machining means and at least one second shaft means are located eccentrically relative to the rotational axis of the reducer head so as to orbit round this axis.

5. The assembly of claim 4 wherein a means is provided for reciprocating said machining means axial-ly upon rotation.

6. The assembly of claim 1 with a reducer head having a centre part kinematically separated from the peripheral part and defined by a low cylindric body with front and side faces and supported by said second shaft means, wherein at least one of the said faces is provided with wood working means

7. The assembly of claim 1 with a reducer head having a centre part defined by a cylindrical body - ?0 -_ with front and side faces and which is kinematically se-parated from the peripheral part, wherein a rotatable shaft, defining said second shaft means, is mounted in said body close to the front face thereof and at right angles to the axis of the body and to the rotational axis of the peripheral part and on which said at least one additional operative means is mounted.

8. The assembly of claim 7 wherein said shaft is driven by motor force and said at least one additional operative means is a machining means.

9. The assembly of claim 8, wherein the additional means is defined by two spaced milling cutters for re-moving wanes.

10. The assembly of claim 2 with a reducer head having a centre part kinematically separated from the peripheral part, wherein said at least one second shaft means is eccentrically mounted in the centre part, said at least one additional operative means is a machining means and the centre part is stationarily, but adjustably in rotation mounted in a mount so that by its ro-tation the relative position of the rotational axes of the peripheral part and of the additional means is ad-justable.

11. The assembly of claim 1 with at least two second shaft means eccentrically mounted in the centre part or portion, wherein a planetary gear is provided for the transmission of torque from the first to the se-cond shaft means.

12. The assembly of claim 1, wherein adjacent the centre part or portion, a planar ring-shaped zone with machining elements is provided at said inner edge of the peripheral part or portion.

13. The assembly of claim 1 with at least one side guide means downstream the reducer head, wherein said guide means is essentially displaceable parallel with and by the same distance as said at least one additional operative means.

14. The assembly of claim 13 wherein said side guide means is pivotally mounted on part partaking in the rectilinear axial displacements of the peripheral part, and said displacements in accordance with the centre part are executed by a pivot motion.

15. The assembly of claim 12 wherein a similar second side guide means is provided downstream the first one and is settable independently of the first one.