Patents by Inventor Erik B. Dahlin

Erik B. Dahlin has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4984472
    Abstract: A Coriolis mass flow rate measuring apparatus including one or more detecting means (46), (48), (56) for detecting conduit detection portion velocities caused by Coriolis forces exerted by a mass flowing through the oscillating conduit, and means (54) operative to measure the time differences between said first and second points in time when respective velocity signals have zero velocity and to use such measurements according to the formula ##EQU1## to indicate the mass flow rate.
    Type: Grant
    Filed: December 4, 1987
    Date of Patent: January 15, 1991
    Assignee: Exac Corporation
    Inventor: Erik B. Dahlin
  • Patent number: 4831885
    Abstract: A Coriolis-type mass flowmeter in which the flow tube is vibrated at a resonance frequency approximately equal to the frequency for forced or natural vibration in a higher anti-symmetric mode, such as the second mode. In the preferred embodiment the flowmeter is symmetrical and has sections of oval cross-section that provide low bending resistance to the vibration at the points where the amplitude of vibration is the largest. The preferred embodiment uses electronic signal detection/processing means that generates two signals proportional to flow tube velocity in the direction of vibration of equal distance but on opposite sides of the plane of symmetry of the tube, generates a sum and a difference of the two signals, integrates the sum, demodulates the integrated signal and the difference of the two signals to produce peak amplitude signals, and divides the peak amplitude signals to produce an output that is proportional to mass flow rate.
    Type: Grant
    Filed: September 24, 1987
    Date of Patent: May 23, 1989
    Inventor: Erik B. Dahlin
  • Patent number: 4803867
    Abstract: A fluid meter, such as a density meter or a Coriolis-type mass flow meter is disclosed in which the fluid tube is mounted to allow for expansion and contraction relative to a base to which opposite ends of the tube are mounted. In the preferred embodiments, a single, rectilinear flow tube measuring section is bounded at each end by a thermally insulating wall having a linear bearing which allows longitudinal axial movement while restraining transverse movement. Disposed distally of the linear bearing relative to the flow tube measuring section is means for accommodating the expansion and contraction of the measuring section. In one embodiment this is in the form of a laterally coiled tube portion. In a serial double-tube flow sensor, three serial rectilinear and parallel sections of the flow tube pass through linear bearings similar to that of the single tube, with arcuate sections joining adjacent rectilinear sections.
    Type: Grant
    Filed: April 28, 1987
    Date of Patent: February 14, 1989
    Inventor: Erik B. Dahlin
  • Patent number: 4711132
    Abstract: A Coriolis mass flow rate measuring apparatus including at least one helically configured loop (30) of conduit, a drive mechanism (42) for causing oscillatory movement of a portion of the loop in a direction normal to the direction of flow through the conduit portion and generally parallel to the central axis of the loop, and one or more detectors (46), (48), (56) for detecting the motion resulting from the Coroilis forces exerted on other portions of the loop as a result of the mass flow therethrough and the oscillatory translation thereof. A strain gage (208) and associated processing electronics are also used in combination with the mass flow rate information to determine the density of the flow.
    Type: Grant
    Filed: September 13, 1985
    Date of Patent: December 8, 1987
    Assignee: Exac Corporation
    Inventor: Erik B. Dahlin
  • Patent number: 4660421
    Abstract: A Coriolis mass flow rate measuring apparatus including at least one elongated and helically configured loop 30 of conduit, a drive mechanism 42 for causing oscillatory movement of a portion of the loop in a direction approximately normal to the direction of flow through the conduit portion and approximately parallel to the central axis of the loop, and one or more detectors 46, 48, 56 for detecting the resulting motion caused by the Coriolis forces exerted on other portions of the loop as a result of the mass flow therethrough and the oscillatory translation thereof.
    Type: Grant
    Filed: September 13, 1985
    Date of Patent: April 28, 1987
    Assignee: Exac Corporation
    Inventors: Erik B. Dahlin, Sidney V. Kaiser, Alan M. Young, Andrew K. Levien
  • Patent number: 4224513
    Abstract: A method of on-line control of opacity of moving sheet material being produced by a paper making machine includes an opacity control loop where an opacity additive is controlled and a basis weight control loop where the stock input to a headbox is controlled. These two control loops are decoupled by means of an opacity to stock feed forward and a basis weight to titanium dioxide feed forward. In addition, the effect of moisture change is decoupled from opacity. The opacity of the moving sheet material is measured by a system which employs a visible source and detector on opposite sides of the sheet. A diffusing window is placed both between the sheet and the source as well as between the sheet and the detector.
    Type: Grant
    Filed: April 6, 1978
    Date of Patent: September 23, 1980
    Assignee: Measurex Corporation
    Inventors: Joseph M. Casey, Erik B. Dahlin
  • Patent number: 4098641
    Abstract: A method of on-line control of opacity of moving sheet material being produced by a paper making machine includes an opacity control loop where an opacity additive is controlled and a basis weight control loop where the stock input to a headbox is controlled. These two control loops are decoupled by means of an opacity to stock feed forward and a basis weight to titanium dioxide feed forward. In addition, the effect of moisture change is decoupled from opacity.
    Type: Grant
    Filed: September 25, 1974
    Date of Patent: July 4, 1978
    Assignee: Measurex Corporation
    Inventors: Joseph M. Casey, Erik B. Dahlin
  • Patent number: 4056714
    Abstract: A process for controlling the dry density of ceiling tile where a delayed measurement of thickness or caliper is compared with an off-line oven dry basis weight measurement of a previously taken sample to provide dry density which is then compared to a dry density target to yield an error signal which updates an on-line wet density indication to provide control of stock flow.
    Type: Grant
    Filed: January 13, 1976
    Date of Patent: November 1, 1977
    Assignee: Measurex Corporation
    Inventors: Al Al-Shaikh, Erik B. Dahlin
  • Patent number: 3947668
    Abstract: Method and apparatus for controlling pulp refiners where a feed forward algorithm compensates for the time delay in the effective action of the base refiners which are coupled to a high frequency compensating tickler refiner by a machine chest which has a significant time lag. In addition, efficiency of the control system is enhanced by providing a simple control method for a complex series parallel matrix of base refiners where the change of specific energy is easily accomplished by a distribution algorithm.
    Type: Grant
    Filed: July 20, 1973
    Date of Patent: March 30, 1976
    Assignee: Measurex Corporation
    Inventors: Al Al-Shaikh, Erik B. Dahlin