Vertically Sliding Closure Patents (Class 294/68.25)
  • Patent number: 10066413
    Abstract: A robot may extrude a tower or column. The robot may include an extrusion nozzle, a positioning system, a climbing apparatus, and a controller. The extrusion nozzle may controllably extrude uncured construction material. The positioning system may controllably cause the extrusion nozzle to traverse a perimeter layer of the tower or column. A climbing apparatus may controllably cause the robot to climb. A controller may autonomously: direct the positioning system to cause the nozzle to traverse the perimeter layer of the tower or column; direct the nozzle to extrude uncured construction material during the traverse; direct the climbing apparatus to cause the robot to climb an incremental amount; and repeat each of the foregoing positioning, extrusion, and climbing steps until the extruded tower or column attains a desired height.
    Type: Grant
    Filed: April 16, 2015
    Date of Patent: September 4, 2018
    Assignee: University of Southern California
    Inventor: Behrokh Khoshnevis
  • Patent number: 7255380
    Abstract: A bailer has a tapered leading end to reduce agitation and turbidity as the bailer is introduced into a body of liquid fluid. A check valve is unseated and admits liquid fluid into the bailer as the bailer enters the liquid fluid. The check valve is seated and seals the liquid fluid within the bailer against leakage when the bailer is retrieved from the liquid fluid. A first embodiment includes a bottom-emptying device that guides liquid fluid in the bailer into a wide-mouth container. A second embodiment includes a bottom-emptying device that guides the liquid fluid into a narrow mouth container such as a vial. In both embodiments, the bottom-emptying device is tapered and engages the outside walls of the tapered leading end of the bailer. This prevents liquid fluid from wetting a user's hands when the bottom-emptying device is used to unseat the check valve.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: August 14, 2007
    Inventor: David W. Pratt
  • Patent number: 6979033
    Abstract: An upper imperforate cap closes the uppermost end of a bailer and a lower imperforate cap closes the lowermost end of the bailer. In a preferred embodiment, screwthreads are formed in the uppermost and lowermost ends of the bailer and complemental screwthreads are formed in the upper and lower caps. By capping the opposite ends of a bailer, the bailer serves as its own container when the sample contained within it is shipped to a laboratory. This eliminates VOC devices, nozzles, and the concomitant contamination that may result from emptying a bailer in the field.
    Type: Grant
    Filed: January 24, 2005
    Date of Patent: December 27, 2005
    Inventor: David W. Pratt
  • Patent number: 6846028
    Abstract: An upper imperforate cap closes the uppermost end of a bailer and a lower imperforate cap closes the lowermost end of the bailer. In a preferred embodiment, screwthreads are formed in the uppermost and lowermost ends of the bailer and complemental screwthreads are formed in the upper and lower caps. In another embodiment, screwthreads are formed in a downspout and complemental screwthreads are formed in an imperforate downspout cap. By capping the opposite ends of a bailer, the bailer serves as its own container when the sample contained within it is shipped to a laboratory. This eliminates VOC devices, nozzles, and the concomitant contamination that may result from emptying a bailer in the field.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: January 25, 2005
    Inventor: David W. Pratt
  • Patent number: 6669255
    Abstract: A bailer collects a column of liquid fluid of predetermined height from a body of liquid fluid at a predetermined depth. The bailer is emptied without contaminating the collected liquid fluid with oxygen. The bailer has two check valves spaced apart from one another by a preselected distance so that it can collect liquid fluid at a predetermined depth below the surface of the body of liquid fluid. A vent opening is formed between the first check valve and the second check valve to enable the bailer to be emptied in the substantial absence of oxygen contamination.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: December 30, 2003
    Inventor: David W. Pratt
  • Publication number: 20030160469
    Abstract: A bailer collects a column of liquid fluid of predetermined height from a body of liquid fluid at a predetermined depth. The bailer is emptied without contaminating the collected liquid fluid with oxygen. The bailer has two check valves spaced apart from one another by a preselected distance so that it can collect liquid fluid at a predetermined depth below the surface of the body of liquid fluid. A vent opening is formed between the first check valve and the second check valve to enable the bailer to be emptied in the substantial absence of oxygen contamination.
    Type: Application
    Filed: February 28, 2002
    Publication date: August 28, 2003
    Inventor: David W. Pratt
  • Patent number: 6601889
    Abstract: An air-tight bailer is filled completely and closed at its open upper end with a flat cap so that no ambient air is trapped in the bailer. A mounting member to which a rope is secured for lowering and lifting the bailer is recessed with respect to the open upper end of the bailer so that it does not interfere with the cap. A disc-shaped protuberance formed on the bottom of the cap fills the recess. An annular groove around the recess receives the rim of the open upper end to enhance an air-tight seal between the cap and the open upper end. In a first embodiment, the bailer is emptied by piercing a thin membrane formed in the cap with a spout device having a trailing end in fluid communication with a container. A second embodiment eliminates the membrane and the spout device.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: August 5, 2003
    Inventor: David W. Pratt
  • Publication number: 20030075940
    Abstract: An air-tight bailer is filled completely and closed at its open upper end with a flat cap so that no ambient air is trapped in the bailer. A mounting member to which a rope is secured for lowering and lifting the bailer is recessed with respect to the open upper end of the bailer so that it does not interfere with the cap. A disc-shaped protuberance formed on the bottom of the cap fills the recess. An annular groove around the recess receives the rim of the open upper end to enhance an air-tight seal between the cap and the open upper end. In a first embodiment, the bailer is emptied by piercing a thin membrane formed in the cap with a spout device having a trailing end in fluid communication with a container. A second embodiment eliminates the membrane and the spout device.
    Type: Application
    Filed: October 24, 2001
    Publication date: April 24, 2003
    Inventor: David W. Pratt
  • Publication number: 20020185878
    Abstract: An upper imperforate cap closes the uppermost end of a bailer and a lower imperforate cap closes the lowermost end of the bailer. In a preferred embodiment, screwthreads are formed in the uppermost and lowermost ends of the bailer and complemental screwthreads are formed in the upper and lower caps. In another embodiment, screwthreads are formed in a downspout and complemental screwthreads are formed in an imperforate downspout cap. By capping the opposite ends of a bailer, the bailer serves as its own container when the sample contained within it is shipped to a laboratory. This eliminates VOC devices, nozzles, and the concomitant contamination that may result from emptying a bailer in the field.
    Type: Application
    Filed: June 11, 2001
    Publication date: December 12, 2002
    Inventor: David W. Pratt
  • Patent number: 6457760
    Abstract: A bailer that is substantially leak-free includes an improved valve housing at its lowermost end. A valve body in the form of a solid or hollow hemispherical ball is mounted at the lowermost end of a straight valve stem. The hemispherical valve body seats in a valve seat that matches the contour of the hemispherical exterior surface of the valve body. The valve body has a preselected specific gravity that enables it to float on the surface of the liquid fluid being sampled when the valve body is unrestricted. The valve stem is slideably received within and guided by a central aperture formed in a central hub of a spider member that spans the hollow interior of the valve housing. The spider is supported about its periphery by an annular shoulder formed in the interior sidewalls of the valve housing. The spider is inserted into the valve housing and pressed against the annular shoulder when the bailer is assembled.
    Type: Grant
    Filed: June 16, 2000
    Date of Patent: October 1, 2002
    Inventor: David W. Pratt
  • Patent number: 6390123
    Abstract: A substantially leak-free bailer includes an improved valve assembly at its lowermost end. A valve body is mounted to the lowermost end of a valve stem and the valve stem is slideably received within and guided by a central bore formed on a support member that spans the hollow interior of the bailer at its lowermost end. The valve body may be hemispherical, frusto-conical, or elongate and downwardly tapered. The valve seat is configured to match the contour of the valve body. An annular ridge circumscribes the valve seat and serves as a barrier to particulate matter so that the valve body sits in the valve seat without interference from such particulate matter.
    Type: Grant
    Filed: September 7, 2001
    Date of Patent: May 21, 2002
    Inventor: David W. Pratt
  • Patent number: 6286880
    Abstract: A bailer that is substantially leak-free includes an improved valve assembly at its lowermost end. In a first embodiment, a valve body in the form of a hemispherical ball is mounted at the lowermost end of a straight valve stem. The hemispherical ball seats in a valve seat that matches the contour of the hemispherical exterior surface of the ball. In a second embodiment, the valve body and the matching valve seat are both frusto-conical in configuration. In a third embodiment, the valve body and matching valve seat are tapered downwardly to form an elongate, narrow slot. A fourth embodiment adds a guide member to the third embodiment structure to ensure seating of the downwardly tapering valve body in its valve seat. In all embodiments, the valve stem is slideably received within and guided by a central bore formed in a support member that spans the hollow interior of the lowermost end of the bailer, and the valve body is covered with a cushioned material of uniform thickness.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: September 11, 2001
    Inventor: David W. Pratt