FI68781B - ANORDNING FOER HAERDNING AV STRAENGPRESSADE KROPPAR - Google Patents

Description

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C (45) Pater UI recessed 11 11 1905 (51) Kv.lk. * / Lnt.CI.4 B 27 N 5/00 FINLAND —FINLAND (21) Patent application - Patentansftkning 762273 (22) Application date - Ansökningsdag 09.08.76 ( FI) (23) Starting date - Giltighetsdag 09.08.76 (41) Made public - Blivit offentlig 13.02.77

National Board of Patents and Registration Date of display and publication. - 31.07.85

Patent- och registerstyrelsen '' Ansökan utlagd och utl.skriften publicerad (32) (33) (31) Privilege claimed - Begärd priority 12.08.75 German L ii ttotasavai ta-Förbunds repub1i ken Tyskland (DE) P 2535989.1 ) (72) Anton Heggenstaller, Muhienstrasse 9, 8891 Unterbernbach,

Federal Republic of Germany1ta-Förbundsrepubliken Tyskland (DE) (7 * 0 Oy Kolster Ab (5 * 0 Equipment for curing extruded parts -Anordning för härdning av strängpressade kroppar

The invention relates to an apparatus for curing extruded bodies consisting mainly of a vegetable material, e.g. a forming and curing channel having fixed and movable, non-contact wall portions, the movable wall portions of which are supported in synchronization with the extrusion piston by tension members.

It is known to mix powdered, granular, fibrous, chip-like and similar textile waste products into a binder, to bring the mixture into the cylinder space of the extruder and to extrude it through the nozzle as an endless rod. This rod with an arbitrary cross-section needs thermal curing to become strong and form-fitting. A device known from DE 2 253 121 2 68781 and particularly suitable for the treatment of plant waste uses a cold-nozzle press for this purpose, the pressing nozzle of which is connected at a distance from the inlet of the curing channel. This curing channel is adapted in cross-section to approximately the pressed bar. It consists of several tubes that are divided and tightened together and heated. At the end of this channel there is a counter-pressing device, for example in the form of a constriction of the tube, the function of which is to slow down the rod being pressed through the curing channel, in order to obtain a denser and smoother rod. However, this object is only partially achieved by the prior art device, since the friction device does not affect the friction conditions between the rod and the inner surface of the curing channel at all. It is known that the extruded body changes in cross-section as it passes from the extrusion nozzle to the outlet end of the curing channel. After leaving the nozzle, the rod first expands, increasing its cross-section. The curing channel must therefore be adapted to this increased cross-section. During curing, most of the moisture in the rod evaporates, which together with the constricting effect of the channel walls again causes a reduction in cross-section. In addition, the curable rod material is subjected to continuously pulsating tensile and compressive stresses. The extruder is subjected to pressure shocks to the rod by means of a compressible substance. However, because the material is somewhat resilient, the rod again tends to release tension during the return stroke of the extruder. The individual particles of the rod therefore bind during a certain relative movement with each other, which is why the desired degree of uniformity is often not achieved or is not sufficiently achieved.

It is therefore an object of the invention to provide an apparatus for curing extruded bodies, in which apparatus the density of the extruded body can be predetermined and also maintained during production as well as possibly changed, and in which apparatus the rod can therefore be cured under more calm conditions.

3,687,81 Since the publication of the DE, the invention is characterized in that the movable wall parts of the curing channel are influenced by an adjustably higher support force during the return stroke of the extrusion piston and by a lower support force during the compression stroke.

The curing channel according to the invention is assembled from a plurality of fixed and movable wall parts which form a curing channel both in the circumferential direction and in the longitudinal direction. Because the wall portions do not touch each other, gaps are formed between their edges through which contact of the heated rod can evaporate. The function of the clamping members adapted to support the movable wall sections is to allow a fixed and possibly variable support pressure to act on the movable wall sections. This makes it possible to change the cross-section of the curing channel along its entire length according to the wall sections used, so that it adapts to the cross-section of the respective bar. If the clamping elements are pneumatic or hydraulic shock generators, the support pressure can be precisely adjusted by means of pressure adjustment. However, other types of tensioning members can be used, e.g. prestressed compression spring packages or the like, the support pressure of which can be adjusted by changing the prestressing or in another similar manner.

If, according to an embodiment of the invention, the clamping members can be adjusted in step with the extruder, the tensioning of the rod as the extrusion piston moves backwards is prevented. As a result, the relative mobility of the individual particles in the rod is substantially reduced and greater uniformity of the rod is achieved during curing. Such adjustment of the clamping members, on the other hand, reduces the friction between the inner surface of the curing channel and the outer surface of the rod during the compression stroke, as the moving wall parts may slightly give way during this phase of movement due to the reduced support pressure of the clamping members.

The clamping members and the extrusion piston are suitably hydraulically supplied from a common pressure source, for which a control device is provided which causes the operating pressure of the clamping members to decrease when the adjustable extrusion pressure is reached or exceeded. In this way, a functional overload protection is provided, which at the same time brings with it the advantage that the desired density and thus the specific gravity of the rod to be formed can be adjusted and monitored in a simple manner.

However, in order not to impair the shape stability of the rod and the hardening of its surface layer, the part closest to the extrusion nozzle of the curing channel has rigid or only slightly flexible channel walls.

Thus, within the scope of the invention, it proves advantageous to fasten or guide the wall parts to vertical and spaced brackets to which the clamping members can be connected. This support leg can advantageously be arranged to move in a guide extending parallel to the curing channel in order to compensate for the expansion of the wall parts in the longitudinal direction of the curing channel due to heating.

Since the wall parts are inserted and supported on such bracket-like and articulated support parts, the curing channel can only be opened by turning and opening the movable part of the bracket, which is advantageous in the event of, for example, a drive rod or a production disturbance. Opening the curing channel also prevents excessive heating, completely independent of the fact that the part of the rod in the curing channel can be easily removed from it. This simple structure of the curing channel is again only possible due to the fact that the individual wall parts do not touch each other.

In a preferred embodiment of the invention, the movable wall part is connected to its own support plate in the region of the supports, and the support plate is suspended by guide bolts on the support part and supported from the outside on the clamping member. In this case, the individual guide bolt can be moved in the axial direction to the part of the support and the support is adjustably supported by a spring. The fixed wall parts are also suitably fitted to the lower bracket part of the support by means of similar support plates or joints.

5,68781

A further advantage is achieved according to the invention when the abutment protruding from the support plate is connected to the side of the support which is turned away from the extrusion nozzle of the support by means of a mutually articulated bearing anchor. This tension anchor holds the support plate and thus the wall part attached to the support plate against the frictional force acting in the extrusion direction, but still offers the possibility that the individual wall part is guided radially or vertically relative to the surface of the rod. Thus, when the clamping member applies a reduced support pressure to the movable wall part or even gives the wall part a certain radial clearance, this wall part can be radially resilient despite the high friction due to the articulated arrangement of the tension anchor, which would not be possible if the movable wall part or its support plate were limited to individual .

Finally, according to the invention, it is advantageous to fit a row of encapsulated heating rods or oil heating lines on the outside of the mold plate according to the upper surface of the wall bar and cover them with insulating plates, etc.

The details of the invention will become apparent from the drawing. In it, the invention is shown schematically and by way of example.

Fig. 1 is a cross-sectional view of a curing channel having wall portions fitted to the supports, Fig. 2 is a cross-sectional view of the modification of Fig. 1 with a different extruder cross-section, Fig. 3 is a cross-sectional view of the curing channel between the supports shown in Fig. 1 and a cross-section. The embodiments of Figures 1 and 3 show the structure of the curing channel 1 for a substantially rectangular extrusion profile, the edges of which are chamfered. This curing channel 1 consists of two fixed wall parts 2 and two movable wall parts 3 which are not in contact with each other in the circumferential direction or in the longitudinal direction. The slits 4 between the wall parts 2, 3 are longitudinally passing grooves through which the moisture in the heated rod can evaporate.

On the surface of the individual wall part 2, 3 there is a mold plate 5 arranged according to the compressible rod, on the outer side of which a number of heating pieces 6 are assembled in the housing 7. This may be, for example, electric heating rods or pipes for passing heated liquid (e.g. contact oil) or hot vapors. The free outer surfaces of the housing 7 are surrounded by insulation plates 8.

The fixed wall parts 2 are connected by connecting joints 9 to the lower part 12 of the bracket 11. The lower part 12 is pivotally mounted by a hinge 14 on the pivoting bracket-like upper part 13. Both support parts 12, 13 are fixedly tightened together by a flange 15 and a screw 16. For each group formed by the wall parts 2, 3, two supports 11 are arranged at a distance from each other, it being assumed that the total length of the curing channel consists of several such successively arranged groups, each of which has two supports. One of these supports 11 is fixedly connected to the base, the other support 11 can, as in FIG. 1, be guided by a guide 17 in which the support leg 18 is arranged to move parallel to the axis of the rod in order to compensate for the thermal expansion of the wall parts 2, 3. In addition, each support 11 can be adjustable in the longitudinal and width directions in order to obtain an exact alignment of the axis of the curing channel 1 with the axis of the extrusion nozzle.

The movable wall parts 3 are connected by connecting joints 9 to support plates, which in turn are adapted to move to the movable upper part 13 of the bracket via guide bolts 19. On the inside, the support plates 10 are held by a abutment end 22. The guide bolt 19 is supported by a nut 23 and a capsule 21 Between the guide bolts 19, the clamping member 24 engages the outside of the support plate 10. This clamping member 24 can be, for example, the piston of a hydraulic cylinder 7 68781 25, which is flanged to the upper part 13 of the support. This clamping member 24 can be used to adjust the frictional force applied by the movable wall parts 3 to the rod through the curing channel. For example, if the clamping member 24 is made as a prestressed compression spring, a limited support pressure is created in the moving wall parts 3 upwards. If the internal expansion of the rod exceeds a normal amount, the movable wall parts 3 can spring outwards and thus reduce friction. If, instead, shrinkage occurs as the cross-section of the bar decreases, the movable wall portions 3 can, due to the biasing force of the clamping members 24, reduce the cross-section of the curing channel and thus provide permanent and controllable frictional contact with the bar.

However, the use of hydraulic or pneumatic clamping members 24, 25 has the particular advantage that they can be adjusted to the pace of the extruder. For example, in the compression stroke of the extruder, the clamping members 24 can be slightly raised and thus reduce the friction between the rod and the wall portions of the curing channel. As a result, the extruder has a relatively small resistance to overcome to move the rod forward in the curing channel 1. The lower the friction, the lower the density of the rod will be. In the return stroke of the extruder, on the other hand, the moving wall parts 3 are pressed tightly against the rod by means of clamping members 24, 25. As a result, the rod in the curing channel 1 is to some extent stressed and the individual particles of the rod are not subjected to any tensile stress, which would make it impossible to control the curing process. Namely, experience has shown that the continuous pulsation of the extruder produces corresponding compressive and tensile stresses on the rod in the curing channel, so that the curing process takes place during the continuous relative movement of the individual rod particles.

If, on the other hand, the rod is tensioned by means of the clamping members 24, 25 during the return stroke of the extruder, at which point the tensile stress would begin to act, the tensile stresses are no longer affected at all or only to a small extent.

The clamping members 24, 25 are expediently supplied from the same pressure source as the piston of the extruder, in which case it is advantageous to use a control device by means of which the support pressure of the clamping members 24, 25 can be adjusted to the extrusion pressure. Namely, the higher the extrusion pressure, the lower the support pressure should be. This can be achieved, for example, by fitting a pressure switch device in the pressure line of the extrusion piston, which acts on the valve fitted to the clamping members 24, 25 and releases its magnets from tension when the adjustable pressure is reached or exceeded. In this case, this valve decreases so that the pressure applied to the tightening members 24, 25 can decrease to a value which can be adjusted by means of a pre-tensioning valve arranged in front of the tightening members 24, 25.

In this way, overload protection is also provided, as well as a medium which ensures a constant density of the rod.

However, it may be advisable to provide the part of the curing channel facing the extrusion direction with rigid or only slightly flexible walls in order to ensure the dimensional stability of the bar and at least the circumferential curing in this area.

In the event of service interruptions or malfunctions, the rod can be relatively easily removed from the curing channel 1. The flange connection 15, 16 of the brackets 11 only needs to be opened, after which the bracket top 13 together with the bracket lower part 12 movable wall parts 3 and fixed wall parts 2 is turned without difficulty. , 3 are not connected.

In the exemplary embodiment of Fig. 2, a cylindrical curing channel 1 for forming and curing a rod is shown. The support plate 10 of the movable wall part 3 is here made a trapezoidal frame in which a semicircular mold plate 5, a housing 7 and a correspondingly shaped insulating plate 8 are fixed. The fixed wall part 2, in turn, is fixedly connected by a joint 26, which can at the same time act as a flange of the lower part 12 of the support. It is clear from this that, according to the structure of the curing channel according to the invention, arbitrary cross-sectional shapes can be used.

The embodiment of Fig. 4 shows how the support plate 10 and thus also the movable wall part 3 can be hung on the support 9 68781 so that due to friction the rod does not take the movable wall part 3 in the extrusion direction, but nevertheless ensures radial movement of the movable wall part 3. For this purpose, the support plate 10 has an outwardly extending lug 27, which is pulled by the traction anchor 29 by means of a joint 30. This tension anchor 29 is articulated to the bearing 28 of the support 11 by means of a second joint 30, this bearing 28 being located on the side facing the extrusion nozzle of the support. In this way, the movable wall part 3, after it is still in effective frictional contact with the rod, can be slightly raised by lifting the tightening member 24 easily and without the essential resistances caused by the rod, even as the rod moves forward. Such a possibility would certainly not exist if a abutment surface were used which was confined over its entire surface to the support.

The curing channel 1 is spaced apart from the extrusion nozzle, thereby providing thermal insulation of the curing channel 1 from the cold extruder. The individual wall parts 2, 3 of the curing channel 1 are also separated from each other by their slits. In this way, the thermal expansion of the wall parts 2, 3 is taken into account.

Claims (10)

10 68781 A device for curing extruded bodies consisting mainly of a vegetable material, e.g. chopped by-products with glue from the wood processing industry, in which device the part closest to the extrusion nozzle is made curing channel (1) with fixed (2) and movable, non-contacting wall parts (3), the movable wall parts (3) of which are supported with tension members (24) guided in synchronism with the extrusion piston, characterized in that the movable wall (1) These parts are adjustably controlled by a higher support force during the return stroke of the extrusion piston and by a lower support force during the compression stroke. Device according to claim 1, characterized in that each individual clamping member (24) comprises a clamping device (25), for example a hydraulically driven piston. Device according to Claim 1 or 2, characterized in that the wall parts (2, 3) are fastened or supported on vertical and spaced-apart supports (11) to which the clamping elements (24) are connected. Device according to claim 3, characterized in that each individual support (11) consists of two articulated parts (12, 13) surrounding the curing channel (1), articulated to each other and tightened, to the lower part (12) of which the support leg (18) is attached. ). Device according to Claim 4, characterized in that the support leg (18) is arranged to move in a guide (17) extending parallel to the curing channel. Device according to one of Claims 1 to 5, characterized in that the movable wall part (3) is connected to the support plate (10) in the region of the support (11) and the support plate (10) is suspended from the support part (13) by guide bolts (19) and supported externally on the clamping member (24). Device according to Claim 6, characterized in that each individual guide bolt (19) is fastened in its axial direction to the upper part (13) of the support and is adjustably supported by a spring (20). Device according to Claim 6 or 7, characterized in that the lug (27) extending outwards from the support plate (10) is connected to the side facing away from the extrusion nozzle (31) of the support (11) by means of a mutually articulated bearing anchor (29). Device according to one of Claims 1 to 8, characterized in that a mold plate (5) is arranged according to the outer surface of the rod to be manufactured to support the wall part (2, 3), in which a row of encapsulated heating rod and (6) or oil heating lines are arranged and is covered with insulation boards (8) or the like. Device according to one of Claims 1 to 9, characterized in that the clamping means (24) and the extrusion piston are adapted to be hydraulically supplied from a common pressure source and that they have a control device which reduces the operating pressure of the clamping means (24) when an adjustable extrusion pressure is reached. or exceeded. 68781 12