Patents Assigned to Valmet Oy
  • Patent number: 4804441
    Abstract: Method and apparatus in the headbox of a paper machine and in its approach pipe system. In the headbox, pulp suspension is fed through the approach pipe system and a pressure screen arrangement, if any, to a distributing header part, from which the pulp suspension flow is conducted through a turbulence generator section and further to a lip section. A pulp suspension jet is discharged from a lip aperture of the lip section onto a forming wire or into a throat defined by a pair of forming wires. At least part of the approach pipe system, the distribution header part, and the turbulence generator section are arranged to have two or several substantially parallel pulp suspension flow passages. The different passages operate substantially simultaneously in parallel, when the headbox has been set to operate in a higher flow rate range.
    Type: Grant
    Filed: September 18, 1987
    Date of Patent: February 14, 1989
    Assignee: Valmet Oy
    Inventor: Markku Lyytinen
  • Patent number: 4804055
    Abstract: An attachment for a tractor comprises a frame which is demountable from the tractor, a hydraulic motor having a power take off shaft mounted on the frame, a pivotal attachment mounting for an upper link of a three point hitch, lifting arms pivotally mounted on the frame for raising and lowering the lower links of the three point hitch by means of swinging link arms connected between the lower links and the lifting arms, hydraulic rams mounted on the frame for raising and lowering the lifting arms, and respective releasable hydraulic couplings connected to the hydrulic motor and to the rams for connection to a hydraulic system of the tractor.
    Type: Grant
    Filed: September 18, 1987
    Date of Patent: February 14, 1989
    Assignee: Valmet Oy
    Inventor: Pentti Kostamo
  • Patent number: 4796342
    Abstract: A press roll for a paper machine suitable for use as a substitute for a granite roll includes an inner roll body having a metallic cylindrical exterior to which a coating is applied formed either only of a metallic component or of a mixture of metallic and ceramic components. Where the coating material includes only a metallic component, such a metallic component is chosen so that a separate ceramic component precipitates during the alloying of the material. The coating material is formulated to obtain a surface energy and polarity component thereof which provide the roll surface with suitable web release properties for particular pulp qualities.
    Type: Grant
    Filed: August 17, 1987
    Date of Patent: January 10, 1989
    Assignee: Valmet Oy
    Inventor: Veijo Miihkinen
  • Patent number: 4793250
    Abstract: A method and apparatus for obtaining substantially uniform profiles of the roll mantles of an adjustable-crown roll and a counter-roll at a nip formed therebetween wherein the bearing distance of the counter-roll is substantially larger than the bearing distance of the adjustable-crown roll and wherein the nip is loaded by load forces applied to one or both rolls, preferably at regions of the bearings. A compensation moment is produced by devices situated within the mantle of the adjustable-crown roll between the bearings thereof loading both end regions of the roll mantle, the magnitude of the moment adjustable by adjusting the moment-producing compensation force such that the profiles of the deflected roll mantles of the adjustable-crown roll and the counter-roll at the nip are substantially uniform.
    Type: Grant
    Filed: April 8, 1987
    Date of Patent: December 27, 1988
    Assignee: Valmet Oy
    Inventor: Juhani Niskanen
  • Patent number: 4791748
    Abstract: The present invention relates to a receiver and a recoil lug for a gun. The receiver and the recoil lug with which the receiver is arranged to be fastened to the stock of the gun, are manufactured as separate pieces in accordance with the invention. A characteristic of the invention is that the receiver is manufactured by cold-hammering, inner and outer surfaces thereof are finished. Another feature of the present invention is that the recoil lug is fastened to the receiver by driving the same to form a tight force fit between the two, with guiding surfaces for the gun barrel being formed onto the receiver and onto the recoil lug. The receiver is manufactured to be substantially symmetrical with respect to a longitudinal axis thereof, with an external, shouldered connecting surface being shaped onto the receiver. An annular inner surface is shaped onto the recoil lug which, together with the connecting surface of the receiver, forms the force fit.
    Type: Grant
    Filed: July 14, 1987
    Date of Patent: December 20, 1988
    Assignee: Sako-Valmet Oy
    Inventor: Martti Leskinen
  • Patent number: 4792380
    Abstract: Fastening of a profile bar to adjustment spindles at a discharge opening of a head box of a paper machine. A series of fastening holes or recesses are made into one edge of the profile bar and provided with chamferings. In the end of the adjustment spindles situated next to the discharge opening, a recess is provided with a series of screws being fitted in one side thereof. These screws are provided with ends coresponding to the chamferings in the fastening holes of the profile bar. A second set of screws coaxial with the first set of screws are provided in an outer wall of the recess, with inner ends of the second set of screws being provided with parts corresponding to the outer chamferings of the fastening holes in the profile bar.
    Type: Grant
    Filed: December 10, 1987
    Date of Patent: December 20, 1988
    Assignee: Valmet Oy
    Inventor: Tapani Tuomikoski
  • Patent number: 4792381
    Abstract: A closed press section of a paper machine for removing water from the paper web passing therethrough. A compact press roll combination is provided with several press nips being formed in association with various rolls, and between which the web runs supported by roll surfaces without substantially long free draws. The press section comprises a first nip formed by two press suction rolls, through which two felts pass, the first felt functioning as a pick-up felt and moving the web from a pick-up point through the first press nip, and the second felt moving the web from the first nip to the second press nip of the press section. The second press nip is formed at a lower circumference of a smooth-surfaced, large diameter center roll, through which the second felt runs.
    Type: Grant
    Filed: September 11, 1987
    Date of Patent: December 20, 1988
    Assignee: Valmet Oy
    Inventor: Juhani Pajula
  • Patent number: 4781793
    Abstract: Method in a paper manufacturing process for improving the properties of the paper, in particular its retention. In the method, the fibre material is passed through a refining and screening system to the head-box arrangement of a paper machine, which comprises one or several head boxes, through which the stock suspension is fed onto a forming wire or into a forming gap (G) between a pair of forming wires (40,41). Two different components are formed out of basic stock which contains substantially all the fibres to be used for the paper to be manufactured. Of these components, one component contains mainly fibres longer than the average distribution of fibre length in the basic stock, while the other stock component contains mainly fibres shorter than average and fines as well, in addition to a possible additive component or components for the stock, if any. The stock component of longer fibres is fed, by means of a multi-channel head box, into direct contact with the forming wire or wires (40,41).
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: November 1, 1988
    Assignee: Valmet Oy
    Inventor: Matti Halme
  • Patent number: 4776069
    Abstract: A piston-glide shoe combination for use in a zone-adjustable variable-crown roll comprising a stationary central axle and a cylindrical roll mantle rotatably mounted on the central axle, the glide shoes of the combinations being loaded by hydraulic fluid pressure against the inner surface of the roll mantle so as to control the distribution of nip pressure in a nip formed by the variable-crown roll and a counter-roll. The piston-glide shoe combination includes an auxiliary chamber arrangement into which the pressure fluid is passed from the lubrication chambers and/or glide surface regions of the glide shoe through ducts so that when the pressure in the lubrication chambers and/or on the glide surface regions of the glide shoe is reduced, the reduced pressure is transmitted through the duct to a particular auxiliary chamber or chambers so that a torque tending to stabilize the play at the glide surface of the glide shoe that causes the reduced pressure.
    Type: Grant
    Filed: May 29, 1987
    Date of Patent: October 11, 1988
    Assignee: Valmet Oy
    Inventor: Jorma Snellman
  • Patent number: 4775834
    Abstract: In a static KWh meter, a pulse width-pulse height multiplicator which forms a pulse width-pulse height-modulated signal proportional to the product of measuring signals proportional to voltage and current intensity, said signal being supplied to a voltage/frequency converter (5), from which is obtained a frequency signal (f) proportional to the power and which controls a counting device (7) indicating the energy consumed. The pulse width-pulse height multiplicator has been carried out without any operator amplifiers in that it contains summing members (R1, R2) for adding together a signal (U.sub.u) proportional to the voltage and a triangle wave (U.sub.o), and an analog switch (10) controlled by the summed signal (U.sub.o +U.sub.u) and which takes samples from a signal (U.sub.i) proportional to the current intensity.
    Type: Grant
    Filed: May 28, 1987
    Date of Patent: October 4, 1988
    Assignee: Valmet Oy
    Inventor: Teuvo Lahti
  • Patent number: 4775773
    Abstract: Method and apparatus for controlling the thickness profile of a web passing through a calendering nip formed by two rolls, in which a variable magnetic flux is directed onto an outer surface on one of the rolls from a magnetic shoe device comprising a plurality of cores situated externally of the roll and over substantially the entire axial length thereof. Each core is spaced a discrete distance from the roll surface, with the magnetic flux acting to induce eddy currents along the surface of the roll, generating heat thereon. The roll diameter is changed over the length of the roll in a manner corresponding to the axial temperature profile of the roll, with the changes in diameter of the roll in turn determining the pressure profile across the calendering nip, and thereby determining the thickness profile of the web passing therethrough.
    Type: Grant
    Filed: October 28, 1986
    Date of Patent: October 4, 1988
    Assignee: Valmet Oy
    Inventor: Matti Verkasalo
  • Patent number: 4767501
    Abstract: An arrangement for equalizing the compression pressure acting on a web passing through a paper machine press nip formed by two opposed press rolls and through which of at least one press fabric passes. At least one resilient loop component passes through the press nip, the resilient loop component having an outer surface facing the web whose hardness is within the range of between 10 to 80 P & J by means of which smallsize variations in the compression pressure acting on the web in the range of up to about 6 mm are equalized. The resilient loop component has a framework layer within its thickness whose hardness is substantially greater than the hardness of the outer surface which faces the web by means of which larger variations in the compression pressure acting on the web are equalized. A press section incorporating the arrangement is also disclosed.
    Type: Grant
    Filed: January 6, 1986
    Date of Patent: August 30, 1988
    Assignee: Valmet Oy
    Inventor: Jorma Laapotti
  • Patent number: 4757585
    Abstract: A variable-crown roll for forming a nip with a counter-roll includes a rotatably mounted roll mantle and a fixed central axle situated within the roll mantle defining a space therebetween in which nip profile adjustment devices, such as hydrodynamic glide-shoes mounted on pistons, are provided. The roll mantle is journaled on the central axle which in turn is supported at its ends at points axially outside of the journaling points of the roll mantle. An annular member is provided between each of the end portions of the central axle within the mantle or an extension thereof. A bearing or bearings for journaling the roll mantle on the fixed central shaft is mounted at each end of the roll between a respective annular part and an end region of the mantle or an extension thereof. Hydraulic power devices are provided at each end of the roll between the annular part and the end portion of the central axle which act in the plane of the nip.
    Type: Grant
    Filed: April 1, 1987
    Date of Patent: July 19, 1988
    Assignee: Valmet Oy
    Inventor: Juhani Niskanen
  • Patent number: 4757582
    Abstract: A method for controlling the transverse thickness profile of paper or other web-like product by controlling temperature, including the axial temperature profile, of the mantle of a roll forming a nip with another roll in the manufacture of the paper or other web-like product includes forming a layer of heat transfer liquid on the inner surface of the mantle under the effect of the centrifugal forces generated by the rotation of the mantle, the layer of heat transfer liquid being divided into separate annular sections, and controlling the temperature of the heat transfer liquid layer of each of the sections. A roll in accordance with the invention includes a cylindrical outer mantle rotatably mounted at its axial ends, a stationary inner shaft situated within the mantle and partitions for dividing a layer of heat transfer liquid formed on the inner surface of the mantle into a plurality of separate annular sections.
    Type: Grant
    Filed: February 10, 1987
    Date of Patent: July 19, 1988
    Assignee: Valmet Oy
    Inventor: Matti Verkasalo
  • Patent number: 4757586
    Abstract: A glide shoe arrangement for a variable crown roll is disclosed. The roll comprises a fixed central axle on which a hollow cylindrical roll mantle is rotatably journalled. A series of piston-glide shoe arrangements are fitted along the length of the roll between the axle and the inner surface of the roll mantle and are adapted to be loaded by hydraulic pressure fluid so that each piston loads a corresponding glide shoe against the inner surface of the roll mantle to control the distribution of nip pressure in a nip formed by the variable crown roll and a counter roll. The piston-glide shoe arrangements are fitted in cylinder bores formed in the axle. Spherical surface bearings are fitted between the loading pistons and the glide shoes, the center of curvature or rotation of the bearing surfaces being located on the side of the glide shoe. A pin-shaped projection is fitted in the loading piston and extends through the spherical bearing.
    Type: Grant
    Filed: April 14, 1987
    Date of Patent: July 19, 1988
    Assignee: Valmet Oy
    Inventor: Juhani Niskanen
  • Patent number: 4757708
    Abstract: The measuring device (2) comprises a sensing element (4) communicating with the process substance as well as a lever-like transfer element (7) connected with the sensing element and arranged to transfer the force acting on the sensing element and generated by the process substance to be measured to a measuring element (6) using the torque applied to the transfer element (7) about its fulcrum. The through hole (8) has a diaphragm (14) of elastic material covering the hole, being in engagement with the transfer member (7) in the position substantially perpendicular to the longitudinal axis thereof and acting as a sealing member separating the portion outside the process substance from the process substance.
    Type: Grant
    Filed: March 17, 1987
    Date of Patent: July 19, 1988
    Assignee: Valmet OY
    Inventor: Matti Hietaranta
  • Patent number: 4757782
    Abstract: Apparatus for coating a web, such as paper or board web, comprises a coating nip formed between a rotating counter roll and a smoothing member, or between two smoothing members, through which the web to be coated is passed with a coating substance being applied to the web before it passes through the nip. The apparatus comprises an arrangement by which the linear load and/or the distribution of the linear load in the coating nip is adjustable to control the quantity and/or the distribution of the quantity of the coating substance applied to the web in the transverse direction thereof. A smoothing member comprises an elongate member extending transversely to the direction of web movement through the apparatus and is flexible with respect to its longitudinal dimension so that the profile of the load distribution in the nip can be adjusted to be relatively steep, i.e, the load in the nip may differ relatively widely at points which are relatively close to each other.
    Type: Grant
    Filed: August 4, 1986
    Date of Patent: July 19, 1988
    Assignee: Valmet Oy
    Inventor: Martti Pullinen
  • Patent number: 4756183
    Abstract: Method and Apparatus for Measuring Permeability to Air of a Wall-Like or Sheet-Like Element, comprising the use of a measurement head including a blower having an air-discharge nozzle, a blade wheel and a variable-speed motor for rotating the wheel to produce an air flow which discharges through the nozzle. Pressure in the blower and speed of blade wheel rotation are detected, with appropriate signals indicative thereof being input to a central unit which then appropriately adjusts speed of rotation of the blade wheel to correspond to a predetermined blower pressure value. Permeability value of the element is then determined at the central unit, based on relationship between the speed measurement signal values, and corresponding permeability values.
    Type: Grant
    Filed: April 18, 1987
    Date of Patent: July 12, 1988
    Assignee: Valmet Oy
    Inventors: Raimo Rajala, Raimo Virta
  • Patent number: 4748736
    Abstract: A press roll for a paper machine includes a cylindrical mantle formed of metal providing the roll with mechanical strength. A coating is provided on the roll mantle, the coating being partially or entirely metallic. The metallic coating is preferably formed of stainless steel containing chromium and provides for a controlled detachment of the paper web from the roll coating as well as durability, i.e., ability to withstand various strains to which the roll surface is subjected. In addition to the metallic component, the roll coating may also include a component or components of ceramic material. A method for manufacturing such a press roll includes the application of the coating to the surface of the cylindrical mantle by band welding wherein the welding admixture band is preferably in the range of between about 30 to 150 mm wide and about 0.5 mm thick.
    Type: Grant
    Filed: August 8, 1986
    Date of Patent: June 7, 1988
    Assignee: Valmet Oy
    Inventor: Veijo Miihkinen
  • Patent number: 4747195
    Abstract: A roll, for use in the dewatering press of a paper machine or a calender roll, having adjustable zones. The roll has a non-revolving massive central axle, on which a substantially cylindrical roll mantle is journalled to rotate. Between the central axis and an inner face of the roll mantle, a loading piston-cylinder group or block arrangement is situated, having pistons which can be loaded by hydraulic fluid pressure against the inner face of the roll mantle so as to adjust distribution of pressure in zones along the roll. The loading piston-cylinder group or block arrangement comprises a substantially elongated or oblong cylinder group or block fitted into an axially-extending groove along the central axle, with the cylinder group or block being a separate component from the central axle itself. The cylinder group or block is supported only in the regions of the longitudinal ends thereof upon the central axle, by way of particular supporting arrangements.
    Type: Grant
    Filed: November 25, 1986
    Date of Patent: May 31, 1988
    Assignee: Valmet Oy
    Inventor: Jorma Snellman