Patents by Inventor Karl M. Prewo

Karl M. Prewo 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: 6696144
    Abstract: The present invention is a low density hybrid airfoil comprising a temperature resistant exterior layer and a tough, high impact resistant interior layer. Specifically, the airfoil comprises a monolithic ceramic exterior layer and a fiber reinforced ceramic matrix composite interior layer. Both the monolithic ceramic and fiber reinforced ceramic matrix composite are low density materials. Additionally, the monolithic ceramic is a high temperature resistant material, and the fiber reinforced ceramic matrix composite is a relatively high impact resistant structure. Encapsulating the airfoil with a temperature resistant exterior layer protects the airfoil in a high temperature environment, and supporting the airfoil with a high impact resistant, fiber reinforced ceramic matrix composite improves the overall impact resistance of the airfoil thereby resulting in a tough, high temperature resistant, low density airfoil.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: February 24, 2004
    Assignee: United Technologies Corporation
    Inventors: John E. Holowczak, Karl M. Prewo, Jayant S. Sabnis, William K. Tredway
  • Patent number: 6672046
    Abstract: A hybrid material tension member for an elevator or other people transportation system using organic fiber and steel material as the load carrying components either discretely or in combined form. Several embodiments are disclosed.
    Type: Grant
    Filed: August 21, 2000
    Date of Patent: January 6, 2004
    Assignee: Otis Elevator Company
    Inventors: Karl M. Prewo, Mark S. Thompson, Pedro S. Baranda, David C. Jarmon
  • Publication number: 20020155269
    Abstract: The present invention is a low density hybrid airfoil comprising a temperature resistant exterior layer and a tough, high impact resistant interior layer. Specifically, the airfoil comprises a monolithic ceramic exterior layer and a fiber reinforced ceramic matrix composite interior layer. Both the monolithic ceramic and fiber reinforced ceramic matrix composite are low density materials. Additionally, the monolithic ceramic is a high temperature resistant material, and the fiber reinforced ceramic matrix composite is a relatively high impact resistant structure. Encapsulating the airfoil with a temperature resistant exterior layer protects the airfoil in a high temperature environment, and supporting the airfoil with a high impact resistant, fiber reinforced ceramic matrix composite improves the overall impact resistance of the airfoil thereby resulting in a tough, high temperature resistant, low density airfoil.
    Type: Application
    Filed: April 24, 2002
    Publication date: October 24, 2002
    Inventors: John E. Holowczak, Karl M. Prewo, Jayant S. Sabnis, William K. Tredway
  • Patent number: 6451416
    Abstract: The present invention is a low density hybrid airfoil comprising a temperature resistant exterior layer and a tough, high impact resistant interior layer. Specifically, the airfoil comprises a monolithic ceramic exterior layer and a fiber reinforced ceramic matrix composite interior layer. Both the monolithic ceramic and fiber reinforced ceramic matrix composite are low density materials. Additionally, the monolithic ceramic is a high temperature resistant material, and the fiber reinforced ceramic matrix composite is a relatively high impact resistant structure. Encapsulating the airfoil with a temperature resistant exterior layer protects the airfoil in a high temperature environment, and supporting the airfoil with a high impact resistant, fiber reinforced ceramic matrix composite improves the overall impact resistance of the airfoil thereby resulting in a tough, high temperature resistant, low density airfoil.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: September 17, 2002
    Assignee: United Technologies Corporation
    Inventors: John E. Holowczak, Karl M. Prewo, Jayant S. Sabnis, William K. Tredway
  • Patent number: 6401871
    Abstract: A tension member for an elevator system has an aspect ratio of greater than one, where aspect ratio is defined as the ratio of tension member width w to thickness t (w/t). The increase in aspect ratio results in a reduction in the maximum rope pressure and an increased flexibility as compared to conventional elevator ropes. As a result, smaller sheaves may be used with this type of tension member. In a particular embodiment, the tension member includes a plurality of individual load carrying ropes encased within a common layer of coating. The coating layer separates the individual ropes and defines an engagement surface for engaging a traction sheave.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: June 11, 2002
    Assignee: Otis Elevator Company
    Inventors: Pedro S. Baranda, Ary O. Mello, Hugh J. O'Donnell, Karl M. Prewo
  • Patent number: 6390242
    Abstract: A tension member for an elevator system has an aspect ratio of greater than one, where aspect ratio is defined as the ratio of tension member width w to thickness t (w/t). The increase in aspect ratio results in a reduction in the maximum rope pressure and an increased flexibility as compared to conventional elevator ropes. As a result, smaller sheaves may be used with this type of tension member. In a particular embodiment, the tension member includes a plurality of individual load carrying ropes encased within a common layer of coating. The coating layer separates the individual ropes and defines an engagement surface for engaging a traction sheave.
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: May 21, 2002
    Assignee: Otis Elevator Company
    Inventors: Pedro S. Baranda, Ary O. Mello, Hugh J. O'Donnell, Karl M. Prewo
  • Patent number: 6386324
    Abstract: A tension member for an elevator system has an aspect ratio of greater than one, where aspect ratio is defined as the ratio of tension member width w to thickness t (w/t). The increase in aspect ratio results in a reduction in the maximum rope pressure and an increased flexibility as compared to conventional elevator ropes. As a result, smaller sheaves may be used with this type of tension member. In a particular embodiment, the tension member includes a plurality of individual load carrying ropes encased within a common layer of coating. The coating layer separates the individual ropes and defines an engagement surface for engaging a traction sheave.
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: May 14, 2002
    Assignee: Otis Elevator Company
    Inventors: Pedro S. Baranda, Ary O. Mello, Hugh J. O'Donnell, Karl M. Prewo
  • Patent number: 6364061
    Abstract: A tension member for an elevator system has an aspect ratio of greater than one, where aspect ratio is defined as the ratio of tension member width w to thickness t (w/t). The increase in aspect ratio results in a reduction in the maximum rope pressure and an increased flexibility as compared to conventional elevator ropes. As a result, smaller sheaves may be used with this type of tension member. In a particular embodiment, the tension member includes a plurality of individual load carrying ropes encased within a common layer of coating. The coating layer separates the individual ropes and defines an engagement surface for engaging a traction sheave.
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: April 2, 2002
    Assignee: Otis Elevator Company
    Inventors: Pedro S. Baranda, Ary O. Mello, Hugh J. O'Donnell, Karl M. Prewo
  • Publication number: 20020000347
    Abstract: A tension member for an elevator system has an aspect ratio of greater than one, where aspect ratio is defined as the ratio of tension member width w to thickness t (w/t). The increase in aspect ratio results in a reduction in the maximum rope pressure and an increased flexibility as compared to conventional elevator ropes. As a result, smaller sheaves may be used with this type of tension member. In a particular embodiment, the tension member includes a plurality of individual load carrying ropes encased within a common layer of coating. The coating layer separates the individual ropes and defines an engagement surface for engaging a traction sheave.
    Type: Application
    Filed: May 24, 2000
    Publication date: January 3, 2002
    Inventors: Pedro S. Baranda, Ary O. Mello, Hugh J. O'Donnell, Karl M. Prewo
  • Publication number: 20020000346
    Abstract: A tension member for an elevator system has an aspect ratio of greater than one, where aspect ratio is defined as the ratio of tension member width w to thickness t (w/t). The increase in aspect ratio results in a reduction in the maximum rope pressure and an increased flexibility as compared to conventional elevator ropes. As a result, smaller sheaves may be used with this type of tension member. In a particular embodiment, the tension member includes a plurality of individual load carrying ropes encased within a common layer of coating. The coating layer separates the individual ropes and defines an engagement surface for engaging a traction sheave.
    Type: Application
    Filed: February 26, 1998
    Publication date: January 3, 2002
    Applicant: Otis Elevator Company
    Inventors: PEDRO S. BARANDA, ARY O. MELLO, HUGH J. O'DONNELL, KARL M. PREWO
  • Patent number: 5950470
    Abstract: The present invention is a method and apparatus for peening the internal surface of non-ferromagnetic hollow parts. Ferromagnetic peening elements are inserted into the non-ferromagnetic hollow part, and a magnetic dipole creates a magnetic field through the non-ferromagnetic hollow part attracting the peening elements which contact a portion of the internal surface of the non-ferromagnetic hollow part. The magnetic field is disengaged and a second magnetic dipole creates a second magnetic field, thereby causing the peening elements to contact a second portion of the internal surface. The magnetic dipoles are repeatedly turned on and off, thereby causing repeated impact within the interior of the hollow part until the internal surface attains a predetermined stress level.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: September 14, 1999
    Assignee: United Technologies Corporation
    Inventors: Karl M. Prewo, Pedro Sainz de Baranda, Vincent C. Nardone
  • Patent number: 5478219
    Abstract: An orbiting scroll is made with a ceramic particle reinforced aluminum metal matrix composite. The resultant part has increased wear resistance, closer thermal expansion matching with cast iron, can be used without tip seals and offers the advantages associated with a reduced mass. In manufacturing the part, the part is pressure cast to a near net shape and machined to the final shape.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: December 26, 1995
    Assignee: Carrier Corporation
    Inventors: Vincent C. Nardone, Karl M. Prewo, James R. Strife
  • Patent number: 5372868
    Abstract: Fiber reinforced glass or glass-ceramic matrix composite articles are described which comprise spaced apart face sheets connected by ribs which extend between the face sheets. The fibers in the ribs are interwoven with the fibers in the face sheets, thereby producing a structure having high shear strength.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: December 13, 1994
    Assignee: United Technologies Corporation
    Inventors: Karl M. Prewo, Otis Y. Chen, Martin J. Gibler, Glenn M. Allen
  • Patent number: 5122226
    Abstract: A process for fabricating a composite article is disclosed. A surface of a preconsolidated fiber reinforced glass matrix composite structure is pretreated to promote adhesion to the surface, a mass of fiber-containing uncured resin is molded in contact with the pretreated surface and the resin is cured to consolidate a fiber reinforced resin matrix composite structure and simultaneously bond the resin matrix composite structure to the glass matrix composite structure. A composite article fabricated by the above process is also disclosed.
    Type: Grant
    Filed: August 12, 1987
    Date of Patent: June 16, 1992
    Assignee: United Technologies Corporation
    Inventors: Eric Minford, Karl M. Prewo, Robert J. Miller
  • Patent number: 5116398
    Abstract: A method of manufacturing a glass or glass-ceramic matrix composite article is disclosed which serves to eliminate the need for an expensive vacuum hot press and to significantly reduce the time required for densification. A preform composed of a mixture of chopped or continuous fibers such as carbon or silicon carbide and glass powder is heated to a temperature sufficiently high to soften the glass powder to a deformable state. Thereupon, the preform is deformed between dies which are at a temperature below that of the preform. A resultant composite article assumes the configuration of the shaped die cavity and is cooled by the natural loss of heat to the dies.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: May 26, 1992
    Assignee: United Technologies Corporation
    Inventor: Karl M. Prewo
  • Patent number: 5079099
    Abstract: A microstructurally toughened ceramic-particle-reinforced metal-matrix composite article is disclosed. The article exhibits a complex microstructure. The article exhibits high tensile strength, high elastic modulus and high impact resistance. A process for making the article is also disclosed. The process includes positioning structural elments within a metallic container to define one or more void spaces within the container, introducing a quantity of metallic particles or of a particulate mixture of metallic particles and ceramic particles into the void spaces, and consolidating the container, structural elements and particles to form the microstructurally toughened composite article.
    Type: Grant
    Filed: February 16, 1989
    Date of Patent: January 7, 1992
    Assignee: United Technologies Corporation
    Inventors: Karl M. Prewo, Vincent C. Nardone, James R. Strife
  • Patent number: 5015116
    Abstract: A dimensionally stable structural joint particularly suited for use in space systems. The joint comprises a connector having at least two tubular sleeves, at least two tubular members, and at least two annular clamping means for securing the tubular members inside the connector. The connector comprises at least two elements, manufactured from a fiber reinforced composite, which, when mated, form the connector. The tubular members are manufactured from a material having a coefficient of axial expansion of substantially zero. The annular clamping means are manufactured from a material having substantially the same coefficient of radial expansion as the tubular members. The combination of the connector comprises at least two elements and the annular clamping means with substantially the same coefficient of radial expansion as the tubular members allows the joint to accommodate radial expansion and contraction while maintaining axial dimensional stability.
    Type: Grant
    Filed: February 26, 1990
    Date of Patent: May 14, 1991
    Assignee: United Technologies Corporation
    Inventors: Vincent C. Nardone, James R. Strife, Karl M. Prewo
  • Patent number: 4999256
    Abstract: A microstructurally toughened ceramic-particle-reinforced metal-matrix composite article is disclosed. The article includes discrete regions of ceramic-particulate-reinforced metal matrix which enclosed within and separated from each other by a network of unreinforced metal. The article exhibits high tensile strength, high elastic modulus and high impact resistance.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: March 12, 1991
    Assignee: United Technologies Corporation
    Inventors: Karl M. Prewo, Vincent C. Nardone, James R. Strife
  • Patent number: 4983463
    Abstract: A process for fabricating a composite article is disclosed. A surface of a preconsolidated fiber reinforced glass matrix composite structure is pretreated to promote adhesion to the surface, a mass of fiber-containing uncured resin is molded in contact with the pretreated surface and the resin is cured to consolidate a fiber reinforced resin matrix composite structure and simultaneously bond the resin matrix composite structure to the glass matrix composite structure. An external flap for a gas turbine engine fabricated by the above process is also disclosed.
    Type: Grant
    Filed: October 13, 1988
    Date of Patent: January 8, 1991
    Assignee: United Technologies Corporation
    Inventors: Eric Minford, Karl M. Prewo, Robert J. Miller
  • Patent number: 4960629
    Abstract: A fiber reinforced glass composite article is disclosed. The article comprises from about 20 volume percent to about 50 volume percent of a glass or glass ceramic matrix, from about 5 volume percent to about 50 volume percent monofilament fiber reinforcement and from about 15 volume percent to about 50 percent yarn fiber reinforcement. The monofilament fiber reinforcement and yarn fiber reinforcement are selectively distributed in the glass matrix to provide a fiber reinforced composite article which exhibits high tensile strength, high elastic modulus, high fracture toughness.
    Type: Grant
    Filed: June 28, 1989
    Date of Patent: October 2, 1990
    Assignee: United Technologies Corporation
    Inventors: David C. Jarmon, Karl M. Prewo