Patents by Inventor Mahlon Denton Dennis

Mahlon Denton Dennis 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: 6315066
    Abstract: The present disclosure sets out a method and apparatus for forming an insert body. The insert body is preferably made of hard particles of tungsten carbide commingled with particles of a binding metal alloy primarily made of cobalt. The finished component typically is a right cylinder of tungsten carbide and cobalt based alloy. It incorporates in it a diamond region which is formed of diamond particles and cobalt also. The geometry of the diamond region is preferably a sphere or a cylinder and has a curvilinear bottom face to distribute stress for structural integrity.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: November 13, 2001
    Inventor: Mahlon Denton Dennis
  • Patent number: 6126895
    Abstract: The present disclosure is directed to a method of converting green particles to form finished particles. The apparatus used for sintering incorporates an elongate hollow tube, an insulative sleeve there about to define an elevated temperature zone, and a microwave generator coupled through a wave guide into a microwave cavity incorporated the tube. The particles are moved through the tube at a controlled rate to assure adequate exposure to the microwave radiation. Another form sintered a solid part in a cavity or mold.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: October 3, 2000
    Assignees: The Pennsylvania State Research Foundation, Dennis Tool Company
    Inventors: Mahlon Denton Dennis, Dinesh Agrawal, Rustum Roy, Jiping Cheng, Paul D. Gigl
  • Patent number: 6066290
    Abstract: This disclosure sets forth a method and apparatus for microwave processing of green work pieces. Typically, individual green work pieces are formed in a small mold cavity crucible, and individual crucibles are then indexed into and out of a tube for a controlled transit time along the tube. The tube extends in one embodiment through a preheater and then into the microwave cavity, the preheater providing an initial heating step to change the rate of absorption of microwave energy so that microwave sintering is accomplished in the cavity.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: May 23, 2000
    Assignees: The Pennsylvania State Research Foundation, Dennis Tool Co.
    Inventors: Mahlon Denton Dennis, Rustum Roy, Dinesh Agrawal, Paul Gigl
  • Patent number: 6063333
    Abstract: This disclosure features a process of making a two part drill bit insert, namely, a body portion of hard particles such as tungsten carbide particles mixed in an alloy binding the particles. The alloy preferably comprises 6% cobalt with amounts up to about 10% permitted. The body is sintered into a solid member, and also joined to a PDC crown covering the end. The crown is essentially free of cobalt. The process sinters the crown and body while preserving the body and crown cobalt differences.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: May 16, 2000
    Assignees: Penn State Research Foundation, Dennis Tool Company
    Inventor: Mahlon Denton Dennis
  • Patent number: 6011248
    Abstract: The present disclosure is directed to the fabrication of a highly wear layer either directly upon an article or tool support structure or body, or as a wear resistant insert or element which is subsequently attached to the tool body. The wear material is formed by sintering particulate material using the absorption of microwave energy as a means of heating. The disclosure also encompasses post manufacture annealing, using heating by microwave radiation, of both highly wear resistant inserts and composite articles which consist of a wear resistant layer and a body. The wear resistant material, whether fabricated directly upon an article or fabricated separately and subsequently affixed to an article, provides an abrasive wear surface and greatly increases the life of the article. Microwave sintered wear resistant surfaces for mills, drills, grinders, brakes, bearings, saw blades and other articles and assemblies are disclosed.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: January 4, 2000
    Inventor: Mahlon Denton Dennis
  • Patent number: 5848348
    Abstract: The present disclosure is directed to the fabrication of a highly wear layer either directly upon an article or tool support structure or body, or as a wear resistant insert or element which is subsequently attached to the tool body. The wear material is formed by sintering particulate material using the absorption of microwave energy as a means of heating. The disclosure also encompasses post manufacture annealing, using heating by microwave radiation, of both highly wear resistant inserts and composite articles which consist of a wear resistant layer and a body. The wear resistant material, whether fabricated directly upon an article or fabricated separately and subsequently affixed to an article, provides an abrasive wear surface and greatly increases the life of the article. Microwave sintered wear resistant surfaces for mills, drills, grinders, brakes, bearings, saw blades and other articles and assemblies are disclosed.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: December 8, 1998
    Inventor: Mahlon Denton Dennis
  • Patent number: 5816347
    Abstract: An insert construction is set forth comprising a right cylinder insert body crowned with a PDC crown bonded thereto defining an interface between the two materials. The interface construction is described in geometric terms. The interface includes irregular curvilinear sided depressions to enhance the interface grip between the two materials thereby reducing shear stress concentration which might damage the PDC crown. Other failure modes are reduced also. Relationships are set forth in the amount, depth, and shape of the depressions.
    Type: Grant
    Filed: June 7, 1996
    Date of Patent: October 6, 1998
    Assignee: Dennis Tool Company
    Inventors: Mahlon Denton Dennis, Eric Twardowski
  • Patent number: 5709279
    Abstract: An insert is defined by the present invention. The insert is an elongate cylindrical body having two end faces. At the extended end, the end face supports a PDC layer which is bonded thereto by brazing or sintering and is formed of PDC material to resist impact or shock loading and to provide a long life. The PDC layer is joined to the insert body at a surface which is defined by a central elevated point, the point being relatively small in diameter or is a point, land wherein said straight radial lines extend downwardly and outwardly therefrom. The intercept of the end face with the outer surface of the insert body is an undulating sinusoidal wave form of multiple sinusoidal cycles. This provides a shock resistant insert construction.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: January 20, 1998
    Inventor: Mahlon Denton Dennis
  • Patent number: 5641921
    Abstract: This invention is directed toward a material which is used to coat or create a surface for machine cutting tools, all types of drill bit teeth, saw teeth, bearing surfaces valve seats, nozzles and the like, thereby producing surfaces which are highly abrasion and erosion resistant. Furthermore, this invention includes some of the possible methods for producing such a material given that the methods and apparatus required provide a significant cost reduction over those required for producing prior art surface materials with similar abrasion and erosion resistant properties. More specifically, the material set forth can be formed at relatively low temperatures and relatively low pressures by sintering mixtures for a relatively short period of time.
    Type: Grant
    Filed: August 22, 1995
    Date of Patent: June 24, 1997
    Assignee: Dennis Tool Company
    Inventors: Mahlon Denton Dennis, Barton Hampshire