Patents by Inventor Robert H. Fletcher

Robert H. Fletcher 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: 5860491
    Abstract: A high pressure, low volume hydraulic lift system and a method for retrofitting a low pressure high volume lift system are provided. The lift system includes a low pressure high volume (LPHV) casing within which is mounted a high pressure ram. The ram is equipped to move a plunger in an axial direction with respect to the casing, without the need for any further reinforcement of the existing casing. The method for retrofitting is effected by removing the pre-existing structure of the LPHV system, cutting a hole in the upper portion of the pre-existing casing, and draining all hydraulic fluid. Thereafter, the pre-existing gland flange and plunger are removed. A high pressure low volume hydraulic cylinder and associated hydraulic line, are then installed in the casing of the pre-existing system. The bottom of the high pressure hydraulic cylinder is mechanically locked to the base of the pre-existing outer casing.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: January 19, 1999
    Assignee: Advantage Lift Systems, Inc.
    Inventor: Robert H. Fletcher
  • Patent number: 5740886
    Abstract: A method of retrofit includes the steps of removing the pre-existing superstructure of the lift system. A hole is then cut in the encasement securing the upper portion of the pre-existing casing. Thereafter, all hydraulic fluid is drained. Thereafter, the pre-existing gland flange is removed. The old plunger is also removed. After the same has been accomplished, there is then provided a high pressure low volume hydraulic cylinder and associated hydraulic line, all of which is positioned within the casing of the pre-existing system. The bottom of the high pressure hydraulic cylinder is mechanically locked to the base of the pre-existing outer casing. A new pump and hydraulic lines are then installed. A new plunger is then added to the new hydraulic cylinder and, with it, an appropriate bearing and guide mechanism which uses the pre-existing casing as an outer guide means for the new plunger.
    Type: Grant
    Filed: July 18, 1996
    Date of Patent: April 21, 1998
    Assignee: Advantage Lift Systems, Inc.
    Inventor: Robert H. Fletcher
  • Patent number: 5573083
    Abstract: An automotive lift system includes a vertically elongated in-ground environment-defining canister having an upwardly directed mouth, an automotive lift, an assembly for selectable detachable suspension of said lift situated substantially upon and about the mouth of the canister, an in-ground anchor of the assembly relative to reactive forces generated by the lift and communicated therefrom through the suspension assembly to the anchor.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: November 12, 1996
    Inventors: Robert H. Fletcher, Glenn Felpel
  • Patent number: 5501296
    Abstract: An automotive lift system includes an environment-defining enclosure having an upwardly directed mouth positioned substantially at work level of the system, the enclosure defining both a longitudinal and a transverse axis. The lift system also includes an in-ground anchoring of the enclosure relative to reactive forces generated by vehicles during lifting by the system, the anchoring disposed substantially at the work level and about the mouth of the enclosure. A rigid support frame is secured upon inner annular surfaces of the anchoring, defining a rigid horizontal plane at the mouth of the enclosure and co-parallel with it. Vertically-oriented cylindrical collars are secured to opposite longitudinal ends of the support frame. Further, a vertically oriented elongated screw drive having an upper end and a lower end, the upper end including an annular thrust bearing, is positioned at about the level of the support frame.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: March 26, 1996
    Assignee: Advantage Lift Systems, Inc.
    Inventor: Robert H. Fletcher
  • Patent number: 5404968
    Abstract: An automotive screw lift system includes a front below ground level cavity having a first depth below a surface level. A track element is secured across a mouth of the front cavity proximally to the front surface level. A trolley is provided which is proportioned for slidable longitudinal movement within the track of the front cavity. Further provided is a rear below ground level cavity having a depth greater than the first depth of the front cavity, the rear cavity disposed along a given longitudinal axis relative to the front cavity. Yet further provided is a cavity enclosure secured upon a top opening of the rear cavity, the enclosure positioned beneath the surface level. Within the front and rear below ground cavities are provided front and rear screw lift assemblies each having a length less than the first depth of the first cavity, each of the lift assemblies having upper ends having flanges selectably interfaceable with either of the trolley or the rear enclosure.
    Type: Grant
    Filed: February 9, 1994
    Date of Patent: April 11, 1995
    Assignee: Advantage Lift Systems, Inc.
    Inventor: Robert H. Fletcher
  • Patent number: 5199686
    Abstract: An automotive lift system includes a longitudinal series of transverse pairs of left and right rigid lifting legs, neither any legs of said pairs of legs nor any longitudinally successive legs having any on-ground connection therebetween, each of the legs having a top and a bottom, each bottom of each leg having, pivotally secured to it, a planer base which is anchored upon an on-ground floor. The system also includes left and right longitudinal vehicle wheel support platforms, the platforms having a pivotal connection relative to the respective tops of each of the respective pairs of left and right rigid legs.
    Type: Grant
    Filed: January 2, 1992
    Date of Patent: April 6, 1993
    Assignee: Advantage Lift Systems Inc.
    Inventor: Robert H. Fletcher
  • Patent number: 5190122
    Abstract: A safety interlock system is provided for enabling ascend or descend interrupt of an automotive lift platform. A interface of negative rake sinusoidal shaped surfaces is employed together with an assembly for selectably placing such surfaces against each other during descent interrupt.
    Type: Grant
    Filed: September 12, 1991
    Date of Patent: March 2, 1993
    Assignee: Andvantage Lift Systems, Inc.
    Inventors: Robert H. Fletcher, James Myers
  • Patent number: 5096159
    Abstract: An automotive lift system includes a number of longitudinal transverse pairs of left and right legs each of which legs, include a top and a bottom. Each bottom is pivotally stationed to a base which in turn is positioned upon a floor. The lift system eliminates the need for torsion bars and provides ease of front-to-back and left-to-right access beneath an automotive vehicle that has been elevated.
    Type: Grant
    Filed: January 18, 1991
    Date of Patent: March 17, 1992
    Assignee: Advantage Lift Systems, Inc.
    Inventor: Robert H. Fletcher
  • Patent number: 4507746
    Abstract: A programmable digital device designed to perform a matched filtering opeion on arbitrary binary phase-coded signals. The technique is used in secure communication systems and for various radar and missile fuzing operations. The essential features minimize the component by the specific networks for the summing units containing unique combinations of digital components. The output is converted to sign-magnitude format.
    Type: Grant
    Filed: July 28, 1982
    Date of Patent: March 26, 1985
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Robert H. Fletcher, Jr.
  • Patent number: 4388622
    Abstract: A double sideband linear frequency modulation technique for radar applications is disclosed for obtaining simultaneous range and doppler measurements. The method of obtaining measurements is useful in a variety of radar applications; however, the most promising area is in continuous wave radar systems. Linear Frequency Modulated (LFM) waveforms of both increasing and decreasing frequency are simultaneously transmitted. Upon reception, these sideband signals are combined coherently to give an output that is a function of the target's radial velocity. The received signals are also processed separately to obtain target ranging information.
    Type: Grant
    Filed: April 15, 1981
    Date of Patent: June 14, 1983
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Robert H. Fletcher, Jr.
  • Patent number: D343488
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: January 18, 1994
    Assignee: Advantage Lift Systems, Inc.
    Inventor: Robert H. Fletcher