Abstract: In a three-phase permanent-magnet synchronous machine, a pole gap and a skew of permanent magnets on the rotor are designed such that oscillating torques which are caused by the fifth and seventh harmonics of the stator field and of the rotor field are mutually reduced. In particular, the skew can be chosen as a function of the pole gap, such that the majority of the respective oscillating torques is neutralized. This results in minimal torque ripple.

Abstract: In order to connect an angle measuring device to a brushless direct-current motor, a coupling is used, the coupling halves (10, 28) of which are each attached to the rotor (46) of the motor and/or the rotor (42) of the angle measuring device. Instead of using a coupling that is rotationally symmetrical at arbitrary angular positions as in the prior art, a coupling is used in which the coupling halves (10, 28) can be connected to one another only in a finite number of relative angular positions. An adjustment must be made before the coupling halves (10, 28) are attached to the respective rotors (46, 52). This allows all subsequent adjustment to be omitted, for example, even for maintenance work.

Abstract: A three-phase dynamoelectrical permanently excited synchronous machine includes a stator with teeth which point to a rotor, wherein twelve slots are formed between the teeth. The slots have coil sides of coils of a winding system in such a manner that two coil sides of different coils are situated in each slot. The rotor has a cylindrical support structure which is provided with permanent magnets defined by an inner radius which corresponds to a radius of the support structure, and by an outer radius which is smaller than their inner radius. The permanent magnets are formed with ten magnet poles when viewed in a circumferential direction.

Abstract: In order to connect an angle measuring device to a brushless direct-current motor, a coupling is used, the coupling halves (10, 28) of which are each attached to the rotor (46) of the motor and/or the rotor (42) of the angle measuring device. Instead of using a coupling that is rotationally symmetrical at arbitrary angular positions as in the prior art, a coupling is used in which the coupling halves (10, 28) can be connected to one another only in a finite number of relative angular positions. An adjustment must be made before the coupling halves (10, 28) are attached to the respective rotors (46, 52). This allows all subsequent adjustment to be omitted, for example, even for maintenance work.

Abstract: In a three-phase permanent-magnet synchronous machine, a pole gap and a skew of permanent magnets on the rotor are designed such that oscillating torques which are caused by the fifth and seventh harmonics of the stator field and of the rotor field are mutually reduced. In particular, the skew can be chosen as a function of the pole gap, such that the majority of the respective oscillating torques is neutralized. This results in minimal torque ripple.

Abstract: Process for homogenizing the property cross direction profile of a continuous web made of paper or cardboard and a paper machine that is suitable for carrying out the above-mentioned process. The process is characterized in that the shrinkage cross direction profile of the material web is homogenized during its manufacturing process by controlling the local composition of the stock suspension sectionally across the width by changing the proportions of components that have different shrinkage behaviors. The paper machine includes an approach flow system having at least two regions that produce different stock suspensions with fiber mixtures that have different shrinkage behaviors. The stock suspension supplies from the approach flow system to the headbox have at least two branches for the at least two different stock suspensions. Near the headbox, a plurality of sectional mixing points are provided, which combine the stock suspensions that have different shrinkage behaviors.

Abstract: An extended nip press for dewatering a pulp web has two press rolls that form an extended nip. The first press roll is retained in the axial direction at least at one end, and is held with its bearing pins on first bearing blocks. The second press roll is also held with its bearing pins on second bearing blocks. The second bearing blocks can be tensioned, each in pairs, with respect to the first bearing blocks by flexurally elastic tension elements, the tension elements allowing a relative displacement of the press rolls in the axial direction. The second bearing blocks are fixed in position with respect to the first bearing blocks in order to prevent excessive bending stress on the tension elements. For this purpose, either the rotary bearings of the second press roll are configured in non-tilting fashion, or additional support bearings are provided.

Abstract: The invention is directed to a drying section of a paper machine for drying a fiber web. The drying section includes a plurality of drying groups, with each drying group having a plurality of heatable drying cylinders and a continuous hold-down belt. The hold-down belt has a longitudinal tension which biases the fiber web against the drying cylinders. The plurality of drying groups include at least one high-pressure group comprising a single-row drying group having one row of drying cylinders and one row of corresponding deflection rolls. The high-pressure group has a corresponding hold-down belt with a longitudinal tension which is at least 10 kN/m.

Abstract: A method for improving the quality of multilayer and multiply papers in the wet section of a paper machine, wherein at least two stock suspensions of different quality are used for producing a paper web. The wire water removed through the paper machine wire is collected in separate vessels and recycled. At least the major part of a first stock suspension is dewatered through a first wire, while at least the major part of a second stock suspension is dewatered through a second wire. The wire water removed through each of the wires is collected, separately from the other wire water, and recycled to the stock suspension of the same layer.

Abstract: A paper machine forming section with two wire forming units. One of the two forming units is a twin wire web forming unit having a headbox, two wire loops arranged in sandwich-like manner and a drainage element for each of the wire loops. The first web-forming unit has a first section including a curved suction drainage element or roll in the first lower wire loop; a second section with opposing drainage ledges, wherein the drainage ledges are stationary on the upper side and the drainage ledges are developed resiliently pressable on the bottom side; the drainage ledges of the upper and lower sides are arranged staggered with respect to each other in the direction of travel of the wire, and at least the ledges of the upper side are developed with suction; a third section which has at least one suction wire separating element on one side. The second web-forming unit is a hybrid former with a single wire.

Abstract: A paper machine forming section with two twin-wire sections for forming a multilayer paper web. Each twin wire web-forming unit consisting of a headbox, two wire loops arranged to define a common wire path for molding the web being formed in sandwich-like manner and drainage elements for each of the wire loops. The common wire path of each web-forming unit has a first section including a curved suction drainage element or roll in the first lower wire loop; a second section including opposing drainage ledges, wherein the drainage ledges are stationary on the upper side and the drainage ledges are developed resiliently pressable on the bottom side; the drainage ledges of the upper and lower sides are arranged staggered with respect to each other in the direction of travel of the wire, and at least the ledges of the upper side are developed with suction; and a third section which has at least one suction wire separating element on one side.

Abstract: A twin-wire section with a first and a second endless wire, for forming a fiber material web of a fiber suspension, notably for forming a ply of a multiply paper or cardboard web, the ply being merged on a third wire with a further ply. In the twin-wire zone formed by the first and second wires, a dewatering box (touching the one wire) that features rigid slats is contained in the loop of the one wire, while in the loop of the other wire there are contained several backing slats which can be pushed flexibly on the other wire, while a loop of one of the two wires contains a forming roll which together with said wire forms a looping zone. The forming roll has a smooth, continuous roll shell. The wire which in the looping zone is outside separates from the web and the inner wire at a distance before the end of the looping zone.

Abstract: A wire section of a machine for making a fiber web, with two continuous wires forming together a twin-wire zone. A dewatering element is pressable on the inside of the wire with at least one surface. The dewatering element features in the direction of travel of the fiber suspension, in interaction with the wires, two dewatering zones. The first dewatering zone is defined by an essentially flat surface, while a second dewatering zone is defined by a surface curving about an axis of curvature in the direction of travel of the fiber suspension. Coordinated with the dewatering element are at least two support axes on which support elements are arranged. Coordinated with the dewatering element is a pivot axis. The pivot axis is stationary as regards the tilting operation, and extends parallel to the separation plane between the first and second dewatering zones and parallel to the wire. The pivot axis is arranged in the area of the axis of curvature.

Abstract: The twin-wire former serves for the production of a web of paper or board. Two wire belts (endless wire loops 11 and 12) form a twin-wire zone with each other. Within the twin-wire zone, the one wire belt (12) travels over rigid ledges (28', 28) which are arranged spaced apart from each other on a water-removal box (18). Within the twin-wire zone, furthermore, the other wire belt (11) travels over several ledges (27) which lie opposite the rigid ledges (28), are supported by means of resilient elements (springs 24, pneumatic pressure cushions, or the like), and can be pressed with a selectable force against the other wire belt. Within one of the wire loops (for instance 11), bridging at least two of the ledges (27) present there, a closed wire support surface (9) is provided. A secondary headbox (10') can be arranged in front of the closed wire support surface (9).

Abstract: A method for transferring a continuously arriving web, specifically a paper or cardboard web, from a finished product roll to a new core rotating at the speed of web travel. The new core bears in the direction of web travel and before the finished product roll on a drum around which loops the web. The web is cut longitudinally, prior to running on the drum, for forming a transfer strip. Before reaching the new core, the transfer strip is severed from the advancing web and passed onto the new core. The web is subsequently cut across its entire width, wherein this cut originates from the longitudinal cut.A drum winder for accomplishing the method wherein the severing device for the transfer strip is arranged before the intake gap between the drum and the new core. A high-pressure water jet is used for severing the transfer strip from the web.

Abstract: An apparatus for winding a continuous web, specifically tear-resistant paper or cardboard web, is preferably designed as a Pope reel winder, and when exchanging a full roll with an empty reel-spool, the latter is in customary fashion placed on the winding drum over which the web initially continues to advance onto the full roll. At the edge of the web, a sickle-shaped catch lever reaches around the upper portion of the empty reel-spool and engages the edge of a web loop to pull it about a portion of the empty reel-spool. Simultaneously, a cutting device can make a transverse cut in the edge of the paper web, and once the web edge has been engaged by the empty reel-spool, the remaining portion of the web tears through essentially without any shock effect.

Abstract: An elongated machine frame has a plurality of uprights which are spaced longitudinally of the frame and subdivide the same into individual sections each provided with a support structure. A first plurality of rollers is cantilevered on the support structures in these sections and an endless felt web is trained about and supported by these first rollers, extending over substantially the length of the machine frame. Each section has an endless upper screen located above the felt web and defining with the same a gap in which a ply formed upon the respective upper screen is laid onto the felt web. The upper screens are each supported by a plurality of second rollers which are also cantilevered on the respective support structures. Cut-outs are provided in the support structure to permit installation and removal of the felt web and the upper screen.

Abstract: A press roll for acting in opposition to a counter roll. The press roll has a support member which is supported at its opposite ends. The support member is stationary in certain most embodiments and rotatable in one embodiment. A flexible, liquid-tight endless press jacket is wrapped around the support member. At each lateral end of the press roll, the press jacket is fastened to the outward end of a supporting disk, which is rotatably mounted on the support member. The lateral edge zones of the press jacket are both deformed radially inwardly around the outside of the respective supporting disks and each edge zone is clamped there by a annular clamping flange. To facilitate deformation of the edge zones, at least one of the edge zones terminates in a series of tongues separated by cutouts arrayed around the roll. Coiled tension springs engage the edge zone and/or the tongues to pull them in the direction toward the axis of the roll.