The invention relates to sets for the mechanical processing, in particular grinding of suspended fibrous material, which serves as a material being treated. Such sets are used in grinding machines, so-called refiners, but also in so-called deflakers and similar devices for the mechanical processing of suspended fibrous material. A set includes a die plate which is configured in the form of a perforated plate or mask and has openings in a predetermined arrangement. Blade-shaped processing elements, which jut out on the process-proximal side, are inserted into these openings and flowed upon by the fibrous material. These blade-shaped processing elements can, optionally, have process-distal foot regions which can protrude beyond the die plate.
A set is known from U.S. Pat. No. 4,681,270 which includes a die plate or perforated plate having openings in a predetermined arrangement. Rod-shaped or blade-shaped processing elements are placed into this die plate and have tongues which project beyond the die plate on the process-distal side. After inserting the foot region of the blade-shaped processing elements through the associated openings in the die plate, the feet protruding from the bottom side are cast with polymer and in part also welded to each other. The slimmer the design of the blade-shaped processing elements, the more difficult it is to keep them on the process-proximal side in a predetermined orientation and at a predetermined constant distance from each other.
U.S. Pat. No. 5,249,734 describes a rotor disc for a refiner and a method for its production. Distance elements are hereby arranged between the blade-shaped processing elements or blade elements in order to form a channel for allowing passage of the material being treated. These distance elements can be integrally formed with dam-shaped parts to enable improved processing of the material being treated. These dam-shaped parts extend orthogonally to the extension of the blade-shaped processing elements. This construction provides only weld connections between the structural elements. Such a production process is both time-consuming and also involves great additional equipment costs.
DE 102 68 324 A1 discloses a die plate with oblong holes, wherein a blade-shaped processing element (refiner rod) is positioned per oblong hole. The refiner plate has a multi-layered sheet metal structure, and the elements to be connected to each other are fixed by welding, preferably laser welding and electron beam welding, gluing and soldering.
DE 197 54 807 C2 describes a set and method for manufacturing sets, which are referred to there as “blade sets”, wherein the fastening step is a vulcanizing process and wherein a polymer is used as a binder.
U.S. Pat. No. 5,921,486 discloses replaceable refiner plates, which include alternately arranged blade-shaped processing elements (refiner rods) and distance elements (distance rods). Together with a carrier plate, the processing elements and the distance elements are connected to one another by a material joint using high-temperature soldering.
The aim of the invention is to provide sets for the mechanical processing, in particular grinding, of suspended fibrous material as mentioned above, which can be realized cost-effectively, have a structure with as few parts as possible, hold the blade-shaped processing elements operationally stable, and in which the assembly of the blade-shaped processing elements has a sufficient inherent bending stiffness.
According to the invention, provided for this purpose is a set for the mechanical processing, in particular grinding, of suspended fibrous material (material being treated), in a refiner, with a die plate (perforated plate) with openings in a predetermined arrangement, in which blade-shaped processing elements, protruding on the process-proximal side and flown upon by the fibrous material (material being treated), are inserted, have process-distal foot regions that jut out beyond the die plate, wherein each blade-shaped processing element has a plurality of longitudinally spaced-apart foot regions, which run through the die plate and extend beyond the die plate on the process-distal side, which set is characterized in that at least some of the foot regions reach into associated receiving grooves of an additional base plate on the process-distal side.
According to an alternative embodiment, a set for the mechanical processing, in particular grinding, of suspended fibrous material (material being treated), in a refiner, is provided with a die plate (perforated plate) with openings in a predetermined arrangement, in which blade-shaped processing elements, protruding on the process-proximal side and flown upon by the fibrous material (material being treated), are inserted, have process-distal foot regions that jut out beyond the die plate, wherein each blade-shaped processing element has a plurality of longitudinally spaced-apart foot regions, which run through the die plate and extend beyond the die plate on the process-distal side, which set is characterized in that transverse stiffening elements are arranged substantially orthogonally in longitudinal direction of the processing elements such that the transverse stiffening elements stabilize the process-distal foot regions of the processing elements.
Common to both sets of the type involved here is, according to the invention, the solution approach that, in order to improve the bending stiffness and the operational stability of the blade-shaped processing elements, which are nowadays increasingly slimmer in design, the blade-shaped processing elements have a plurality of foot regions which are spaced apart in longitudinal direction and of which at least some are stabilized on the process-distal side by receiving grooves of a base plate such that the overall arrangement of the blade-shaped processing elements is reliably in spaced-apart relation to one another and stiffened in itself.
Transverse stiffening elements, which extend substantially orthogonally in the longitudinal direction of the processing elements, can be arranged on the process-distal side. These transverse stiffening elements extend preferably through the foot regions of the processing elements and hold and support the processing elements spaced-apart relation. In such an embodiment, a kind of lattice arrangement is established on the process-distal side of the die plate by extending the transverse stiffening elements through the foot regions of the processing elements on the process-distal side to thereby improve and strengthen the overall stability of the set design. Overall, the set according to the invention can be constructed with fewer parts and can therefore be produced cost-effectively with simplified structure.
According to a preferred embodiment, the transverse stiffening elements are designed in the form of a dam, jut out beyond the die plate on the process-proximal side, and hold and support the processing elements on the process-proximal side.
In such a configuration of the set, the transverse stiffening elements fulfill a dual function, namely, on one hand, a transverse stiffening on the process-distal side as a result of the transverse stiffening elements and, on the other hand, also a transverse stiffening of the processing elements on the process-proximal side. In this way, sufficient stability can be realized, even when the processing elements are designed extremely slim, i.e., have slight material thickness and great structural height.
According to a preferred embodiment, the assembly of processing elements, die plate, and transverse stiffening elements is cast with a polymer mass on the process-distal side. The lattice-structure-like assembly of processing elements, die plate, and transverse stiffening elements allows for a better adhesive joint by the presence of the cast polymer, without encountering excessive shrinkage phenomena and warping phenomena. Adhesion breaks between metal and adhesive or resin can be reliably reduced.
The residence time of the fibrous material can be influenced in dependence on the number, the arrangement, and the process-side overhang height of the transverse stiffening elements, wherein the suspension speed between adjacent blade-shaped processing elements is reduced by deflection and backup, when a greater number of dam-like transverse stiffening elements are involved. When the distance between the dam-like transverse stiffening elements is selected smaller, the effectiveness and the capacity of the refiner are influenced accordingly.
When, for example, the upper side of the dam-like transverse stiffening element is arranged on half of the overhang height of the blade-shaped processing element, the dam-like transverse stiffening element acts as a flow barrier, whereas in other cases, the surface of the dam-like transverse stiffening elements can also act as an additional processing surface or grinding surface. The dam-like transverse stiffening elements support the blade-shaped processing elements against bending to thereby improve stability, which is particularly advantageous when slim blade-shaped processing elements are involved. As the blade-shaped processing elements and the dam-like transverse stiffening elements form a union, mutual stabilization and an increase in the resistance torque against bending stress are realized.
The process-side overhang height of the processing elements is preferably 6 to 12 mm, preferably 8 to 10 mm. The width of the processing elements can be 1 to 6 mm, preferably 1 to 2.5 mm. According to a further preferred embodiment, the channel width between the processing elements is 1.5 to 6 mm, preferably 1.8 to 2.5 mm.
According to a preferred embodiment, the dam-like transverse stiffening elements physically form a cohesive structure, thereby simplifying installation and handling.
In particular bushings for force introduction of fastening screws for fastening the sets to the corresponding component of the refiner are mounted in openings of the die plate.
These bushings can, preferably, be connected to the die plate by a material joint or a combination of material joint and form fit. A welded connection, soldered connection and/or adhesive bond are suitable as material joint.
Preferably, the bushings have each an anti-rotation mechanism, and this anti-rotation mechanism can be realized by a polygonal connection or a polygonal shape, so that the bushings are fixed in place in rotation direction after installation in the openings of the die plate.
In summary, it is essential in the sets according to the invention that the individual blade-shaped processing elements are inserted with the assistance of a plurality of longitudinally spaced-apart foot regions into the base plate which is combined therewith, with these processing elements being fixed in a stabilized manner on the process-distal side on the perforated plate or, optionally, are additionally designed by transverse stiffening elements on the process-distal side such as to have sufficient bending stiffness and operational stability. Furthermore, when the dam-like transverse stiffening elements are structurally linked together as a chain or strip, installation and handling are also simplified.
Overall, the invention realizes a structure which can be implemented cost-effectively and in which the blade-shaped processing elements are supported and held rigidly when used in operation.
Further details, features, and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings, without any limiting character. It is shown in:
In the figures of the drawing, same or similar parts are designated by the same reference numerals.
An embodiment is shown with reference to
An embodiment variant of a set 1′ is shown with reference to
For sake of clarity, with reference to
Finally,
In the embodiment of the bushing 6′ according to
An embodiment variant or an alternative embodiment of a set 1″ is schematically shown and explained with reference to
In the embodiment variant and preferred embodiment of the set 1′, 2 according to
The invention is not limited to the above-described details of the preferred embodiments but numerous changes and modifications are possible, which the artisan can contemplate, if need be, without departing from the spirit of the invention. For example, blade-shaped processing elements 3 and dam-like transverse stiffening elements 4 can be combined with one another, which partly jut out on the foot region 10 for the die plate 2 on the process-distal side 14, and those shown in
An essential feature of the invention is that the assembly of die plate 2, blade-shaped processing elements 3, 3′ and, optionally, dam-like transverse stiffening elements 4 ensures effective mutual stiffening, which is due to the lattice-like structure of the assembly according to the invention or the anchoring of at least a number of the longitudinally spaced foot regions 10 of the blade-shaped processing elements 3, 3′ in an additional base plate. Furthermore, when the dam-like transverse stiffening elements 4 are physically held together into a linked structure, installation of such a set 1, 1′ is facilitated. In addition, the transverse stiffening elements 4 also have sufficient inherent stiffness. By intermeshing blade-shaped processing elements 3 and dam-like transverse stiffening elements 4, a surprisingly good inherent stiffness is obtained in the set 1, 1′ according to the invention, even in the case that the blade-shaped processing elements 3 are designed very slim, i.e. have a slight thickness dimension in relation to the length and height dimensions.
Number | Date | Country | Kind |
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10 2014 009 588.6 | Jun 2014 | DE | national |
This application is a divisional of prior filed copending U.S. application Ser. No. 15/315,212, filed Nov. 30, 2016, the priority of which is hereby claimed under 35 U.S.C. § 120 and which is the U.S. National Stage of International Application No. PCT/EP2015/001276, filed Jun. 24, 2015, which designated the United States and has been published as International Publication No. WO 2015/197192 and which claims the priority of German Patent Application, Serial No. 10 2014 009 588.6, filed Jun. 27, 2014, pursuant to 35 U.S.C. 119(a)-(d).
Number | Date | Country | |
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Parent | 15315212 | Nov 2016 | US |
Child | 15941977 | US |