Patents Assigned to C.H. Heist Corp.
  • Patent number: 5588593
    Abstract: A safety apparatus for use in a hydrocutting or hydroblasting system which has a normally closed shutoff valve for coupling a high pressure water source to a hydrocutting or hydroblasting gun. The shutoff valve is controlled by a solenoid valve coupled between an air-to-open (ATO) input of the shutoff valve and an air power source. A normally open inductive proximity switch, through a relay circuit, provides a control signal to the solenoid valve. The inductive proximity switch is located near a cutting or cleaning nozzle of the gun. When the inductive proximity switch comes in close proximity of a metal object to be cleaned or cut, the proximity switch closes, thereby opening the solenoid valve and the shutoff valve. When the gun is removed from the physical proximity of the metal, the inductive proximity switch opens, thereby turning off the shutoff valve.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: December 31, 1996
    Assignee: C.H. Heist Corp
    Inventor: Thomas B. Boisture
  • Patent number: 5582349
    Abstract: An improved hydroblasting gun having an on/off safety switch system. The on/off switch system comprises at least two actuatable triggers each displacing a specified volume of incompressible fluid which, when coupled with a predetermined volume within an actuator, displaces a piston initiating a signal. In specific application, two separate triggers are depressed displacing a predetermined volume in an actuator adjacent a shut-off valve. Until the actuator fully opens the shut-off valve, hydroblasting operations may not begin. In this manner, the chances of accidental discharge through the depression of a single trigger are eliminated and preferred ergonomical characteristics are provided.
    Type: Grant
    Filed: October 2, 1995
    Date of Patent: December 10, 1996
    Assignee: C. H. Heist Corp
    Inventor: Thomas B. Boisture
  • Patent number: 5535949
    Abstract: An improved safety switch system for hydroblasting and hydrocutting operations. The switch system comprises at least two actuatable triggers each displacing a specified volume of incompressible fluid which, when coupled with a predetermined volume within an actuator, displaces a piston initiating a signal. In specific application within a hydroblasting gun, two separate triggers are depressed displacing a predetermined volume in an actuator adjacent a dump valve. Until the actuator fully closes the dump valve, hydroblasting operations may not begin. In this manner, the chances of accidental discharge through the depression of a single trigger are eliminated and preferred ergonomical characteristics are provided.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: July 16, 1996
    Assignee: C. H. Heist Corp.
    Inventor: Thomas B. Boisture
  • Patent number: 5381811
    Abstract: A furnace cleaning apparatus for cleaning a cyclone furnace with a fluid from a fluid source. The furnace cleaning apparatus comprises a beam assembly capable of being pivotably mounted to the cyclone furnace. A rotary actuator is connected to the beam assembly for turning the beam assembly. A trolley is movably mounted to the beam assembly. A chain drive assembly and a drive source for moving the trolley relative to the beam assembly are mounted to the beam assembly. An articulated arm assembly is pivotally connected to the trolley. A rotary actuator is mounted to the articulated arm assembly for pivoting the articulated arm assembly relative to the trolley. A nozzle is connected to a second end of the articulated arm assembly. A fluid conduit connects the nozzle to a fluid source.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: January 17, 1995
    Assignee: C.H. Heist Corp.
    Inventor: Thomas B. Boisture
  • Patent number: RE36465
    Abstract: A furnace cleaning apparatus for cleaning a cyclone furnace with a fluid from a fluid source. The furnace cleaning apparatus comprises a beam assembly capable of being pivotably mounted to the cyclone furnace. A rotary actuator is connected to the beam assembly for turning the beam assembly. A trolley is movably mounted to the beam assembly. A chain drive assembly and a drive source for moving the trolley relative to the beam assembly are mounted to the beam assembly. An articulated arm assembly is pivotally connected to the trolley. A rotary actuator is mounted to the articulated arm assembly for pivoting the articulated arm assembly relative to the trolley. A nozzle is connected to a second end of the articulated arm assembly. A fluid conduit connects the nozzle to a fluid source.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: December 28, 1999
    Assignee: C.H. Heist Corp.
    Inventor: Thomas B. Boisture