Patents Assigned to Graco Inc.
  • Patent number: 5240390
    Abstract: An air control valve for directing air flow in a double-acting reciprocable motor, where the valve has a first link which is pivotally connected at one end to the motor and mechanically coupled along its length to a reciprocable motor member; a second link pivotally connected to the same point as the first link, and having an over-center spring detent mechanism to position it in either of two pivot positions; both of the links having alignable transverse slots, with a compression coil spring engaged in both slots; and a slide valve member attached to the second link and pivotally movable therewith, to direct the air flow into either of the double-acting motor drive members, the air valve toggling to its second position near the end of the motor drive stroke to cause the motor to reciprocate in the other direction.
    Type: Grant
    Filed: March 27, 1992
    Date of Patent: August 31, 1993
    Assignee: Graco Inc.
    Inventors: Daniel J. Kvinge, Marlin R. Melquist, Steve P. Plager
  • Patent number: 5228622
    Abstract: A control system for a mechanically-driven liquid pump coupled to an air spray gun wherein the control system includes an air pressure monitor to detect air flow to the spray gun and an electrically-operated solenoid valve to relieve liquid pressure in the spray gun liquid delivery line when the spray gun is inoperable, and to control a clutch mechanism to drive the pump when the spray gun is operable or when the pump is being primed.
    Type: Grant
    Filed: June 19, 1992
    Date of Patent: July 20, 1993
    Assignee: Graco Inc.
    Inventors: Edward P. Murphy, Albert W. Lubenow
  • Patent number: 5222841
    Abstract: A system is provided for a set of form tools which utilize a common shank to be able to machine a number of different shapes. A pad is provided which sits between the cutting tool and the shank where the pad is of such a shape and dimension as to provide support for the cutting member, the shank being merely a mounting device. The cutting member and pad may be wider or narrower than the shank and may either extend forward of the shank or behind the forward edge of the shank.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: June 29, 1993
    Assignee: Graco Inc.
    Inventor: Boris E. Simkhovich
  • Patent number: 5222518
    Abstract: An air valve having a runaway control feature, including a movable piston which is insertable into air blocking position in a valve passage, a diaphragm separating two chambers, one chamber being coupled to the air passage upstream of the movable piston and the other chamber coupled to the air passage downstream of the movable piston, a rod movable by the diaphragm to activate a second air valve, the second air valve controlling the flow of air from the air passage upstream of the piston valve to the piston valve itself, thereby forcing the piston valve to move into air closure position in the passageway when the pressure drop upstream and downstream of the piston valve exceed predetermined limits. The invention includes a test feature which includes a third valve for manually unbalancing the air pressure across the diaphragm chambers to simulate the runaway air flow condition and thereby actuate the piston valve closure.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: June 29, 1993
    Assignee: Graco Inc.
    Inventors: Joel T. Fisher, Richard D. Lewis, Charles Rescorla
  • Patent number: 5220259
    Abstract: A DC motor drive system for providing an enhanced motor speed/torque relationship, where circuits modify the motor field winding control switching sequence to compensate for speed effects on motor torque output and to compensate on transient loading effects on motor torque output, and to compensate for rotor inertial effects caused by transient motor load changes.
    Type: Grant
    Filed: October 3, 1991
    Date of Patent: June 15, 1993
    Assignee: Graco Inc.
    Inventors: Neal A. Werner, Gary W. Box
  • Patent number: 5218305
    Abstract: An electrostatic spray gun having a self-contained power supply including a high voltage electrostatic voltage and current source, with circuits for monitoring the voltage and current and developing a frequency signal based on the monitored voltage and current, circuits for modulating the frequency signal with a radio frequency carrier and transmitting the modulated-carrier signal to a remote radio receiver, where the signals are demodulated and converted to a digital display representation of the monitored voltage and/or current.
    Type: Grant
    Filed: November 13, 1991
    Date of Patent: June 8, 1993
    Assignee: Graco Inc.
    Inventor: Lawrence J. Lunzer
  • Patent number: 5213480
    Abstract: A small wheelable line striper is provided with a gasoline engine powered pump which has an outlet designed for direct immersion into a container of paint or other coating material. The gasoline engine and pump are mounted on a pump frame which is attached to two telescoping posts so that the pump and engine may be lifted upwardly out of the bucket of paint. The pump frame is biased upwardly by a nitrogen gas spring which provides an upward force slightly greater than the weight of the engine and pump so that the pump may be lifted automatically. Latches are provided to latch the pump and engine in either the upward or downward positions.
    Type: Grant
    Filed: June 8, 1992
    Date of Patent: May 25, 1993
    Assignee: Graco, Inc.
    Inventors: John A. Yedinak, Mark B. Snyder, Arthur W. Paape
  • Patent number: 5209152
    Abstract: An air operated reciprocating piston pump having a differential area piston is provided with an annular shaped airfoil device having a chevron cross-section and which is located beneath the bottom air intake plate to utilize increasing air velocity at the initiation of bottom changeover in order to assure more reliable changeover.
    Type: Grant
    Filed: March 31, 1992
    Date of Patent: May 11, 1993
    Assignee: Graco, Inc.
    Inventor: Andrew M. Olson
  • Patent number: 5193908
    Abstract: A rotary agitator for use in sealed containers such as drums having a single bung opening. The agitator is provided with a housing which screws into the bung opening and appending from the housing is a rotating hollow shaft having a helical agitator flight or other agitator member which may be inserted through the bung opening. Material from inside the drum or container may be withdrawn upwardly through the hollow shaft and then outwardly through a port in the housing. A check valve is provided in the housing which communicates with the interior of the container in which to allow pressure equalization in the container which may be connected to a source of inert gas or the like to prevent degradation or other harm to the material in the drum which might be caused by ambient atmosphere.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: March 16, 1993
    Assignee: Graco Inc.
    Inventors: Charles L. Rescorla, Irving F. Snyder
  • Patent number: 5189943
    Abstract: An air operating reciprocating motor which is used to drive reciprocating piston pumps or other such devices has located in the exhaust passage thereof a liner made of a flexible elastomeric material. The inside surface of the liner which routes the exhaust area is generally smooth and the outside surface of the liner is spaced from the surface of the passage in which it is located by a number of spacer elements such as rounded knobs. The material between the spacing elements is then allowed to flex when the exhausted relatively high pressure air passes through, thus continually flexing the liner with every cycle of the motor and preventing the buildup of ice in the exhaust passage.
    Type: Grant
    Filed: July 31, 1992
    Date of Patent: March 2, 1993
    Assignee: Graco Inc.
    Inventor: Frederick A. Powers
  • Patent number: 5176176
    Abstract: A back pressure regulator is provided which utilizes laminar flow at all times to minimize degradation of paint which might have metallic particles passing there through. The pressure drop across the regulator is accomplished by utilizing this viscous friction rather than velocity change through an orifice as is common with a conventional pressure regulator.
    Type: Grant
    Filed: November 14, 1991
    Date of Patent: January 5, 1993
    Assignee: Graco Inc.
    Inventors: Richard D. Lewis, James P. Korzenowski
  • Patent number: 5161450
    Abstract: A device to prevent freezng of a reciprocating air motor which drives a reciprocating plunger pump for liquid pressurized transport in which a passage exclusively for exhaust which is connected to an exhaust passage and a exhaust pipe which is connected to this passage exclusively for exhaust are installed, as is a compressed air switch valve and an air tube which supplies hot air to the exhaust passage.
    Type: Grant
    Filed: July 15, 1991
    Date of Patent: November 10, 1992
    Assignee: Graco, Inc.
    Inventor: Yasuo Ishikawa
  • Patent number: 5158438
    Abstract: An easily adjustable and serviceable plural component pumping system has a frame assembly with a pivotable drive beam. The drive beam passes through spherical rod bearings in the connecting rod of two positive displacement pumps. The pumps are mounted to the frame via hand tightenable clamps so that by loosening the clamp the pumps may be slid along the frame to vary the ratio or remove for servicing without the need for too.
    Type: Grant
    Filed: August 2, 1991
    Date of Patent: October 27, 1992
    Assignee: Graco Inc.
    Inventors: Andrew Olson, Lawrence Kelly
  • Patent number: 5154532
    Abstract: The reciprocating pump shaft is joined to a reciprocating motor shaft by the coupling of this invention. The pump shaft is provided with a knob-like end having a chamfered angle between the knob and a reduced diameter section adjacent the knob. A two piece annular collar that's about the chamfered shoulder and the reduced diameter section and the collar is provided with a chamfered shoulder having a slight angular mis-match with the shaft shoulder. A nut draws the pump shaft upwardly against the end of the motor shaft and is tightened to the point where the pre-load between the two shafts is greater than the alternating load imposed by the motor.
    Type: Grant
    Filed: May 14, 1990
    Date of Patent: October 13, 1992
    Assignee: Graco, Inc.
    Inventors: Thomas J. Schaefer, Calvin S. Hulburt
  • Patent number: 5147188
    Abstract: A reciprocating priming piston pump is provided with a piston check valve which provides improved performance by minimizing the pressure drop there through. A dog-bone shaped seat is slideably located inside a piston which in turn slides inside the cylinder of the pump. The piston is restrained at one end by seating upon the valve seat and its outer end by contact with the displacement rod. Rounded surfaces on the valve seat contribute to smooth flow and a slotted guide fingers in the upper end of the piston allow ample flow into the upper chamber from the lower chamber.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: September 15, 1992
    Assignee: Graco Inc.
    Inventor: Thomas J. Shaefer
  • Patent number: 5145339
    Abstract: A multiple piston cylinder reciprocating pump is provided with a cam drive such that the sum of the velocities during the pumping strokes of all of the cylinders is generally constant. The leak free design is provided by utilizing a diaphragm attached to the piston between the main seal assembly and the cam. A flow through intake design is provided which flows incoming material around the piston between the diaphragm and the main seal to prevent the build-up and hardening of material on the piston and in the seal area. The intake and exhaust passages are arranged such that air pockets cannot be formed and any air bubbles which find their way into the pump will rise upwardly out of the pump without restriction.
    Type: Grant
    Filed: November 8, 1990
    Date of Patent: September 8, 1992
    Assignee: Graco Inc.
    Inventors: Kenneth E. Lehrke, Bruce A. McFadden
  • Patent number: 5141161
    Abstract: A spray gun designed for high volume low pressure (HVLP) use is provided with a simple yet effective mechanism for providing feathering as well as allowing for extended needle and nozzle life. A poppet member is spring biased and moves some distance to first initiate air flow prior to initiation of fluid flow. The needle nozzle combination is provided with geometry such that the location of highest velocity is separate from the seating area so as to minimize wear of the seating areas and thus extend life. A two stage pressure drop is utilized for use with plant air. The two stage drop provides more consistent results.
    Type: Grant
    Filed: April 10, 1991
    Date of Patent: August 25, 1992
    Assignee: Graco Inc.
    Inventors: Richard D. Anderson, Carl D. Jacobsen
  • Patent number: 5121930
    Abstract: An air operated dispense head for dispensing of hot melt and related adhesives is provided which utilizes a drop-in seal cartridge assembly in which a hardened needle is sealed using a pair of quad seals along with soft back up rings. Improved life is obtained from this combination of elements.
    Type: Grant
    Filed: May 17, 1990
    Date of Patent: June 16, 1992
    Assignee: Graco Inc.
    Inventors: Gary A. Russell, Paul J. Donley
  • Patent number: 5117998
    Abstract: The wiper plate is designed for ue with a variety of five gallon pails including both straight and tapered pails as well as with either cart applications or with rams. One unit allows a variety of pails to be utilized with the one device. Primary and secondary wipers provide continued contact with a tapered pail. For straight sided pails, a reversible tapered spacer provides varying wiper flexibility depending on whether the unit is going to be used with the ram or cart-mounted pail.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: June 2, 1992
    Assignee: Graco Inc.
    Inventor: James J. Handzel
  • Patent number: 5099783
    Abstract: A doctor blade for use in an adhesive screen printing apparatus is formed of a main blade member of spring steel along with a U-shaped cap. The cap is ideally formed of a filled nylon material and is attached to the blade member with a silicon RTV compound. The use of this construction results in much more even laydown of adhesive from pattern to pattern and from the left and right hand sides of the screen. Use of the invention also serves to increase screen life.
    Type: Grant
    Filed: April 17, 1990
    Date of Patent: March 31, 1992
    Assignee: Graco Inc.
    Inventor: Robert A. Bourgeois