Robotic wash cell using recycled pure water

• US 6,804,579 B1
• Filed: 10/16/2002
• Issued: 10/12/2004
• Est. Priority Date: 10/16/2002
• Status: Active Grant

• Current Assignee: ABB Incorporated (ABB Limited)
• Original Assignee: ABB Incorporated (ABB Limited)
• Inventors: Laski, Stephen J.
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Marc, McDieunel, Marc, McDieunel
• Application Number:
  US10/271,517
• Time in Patent Office: 727 Days
• Field of Search: 700/245, 700/256, 700/258, 700/259, 700/247, 318/568.11, 318/568.12, 318/568.16, 318/587, 342/418, 342/457, 356/237.2, 356/446
• US Class Current: 700/245
• CPC Class Codes: B08B 3/024 Cleaning by means of spray elements moving over the surface to be cleaned
• CPC Class Codes: B08B 3/14 Removing waste, e.g. labels, from cleaning liquid; Regenerating cleaning liquidstreatment of water in general C02F
• CPC Class Codes: B25J 9/0018 Bases fixed on ceiling, i.e. upside down manipulators
• CPC Class Codes: G05B 2219/45013 Spraying, coating, painting

Abstract

The present invention pertains to a robotic wash cell including a six-axis robotic arm and end effector equipped with nozzles that spray unheated, solvent free, pure water at high-pressure to clean or debur objects by maintaining the nozzles in close proximity and substantially normal to each surface being cleaned or edge being deburred. The robotic cell wash is particularly useful for cleaning contaminants such as oil and grease from items having more complex shapes. The six-axis robotic arm positions the nozzles and their sprays substantially normal to each surface being cleaned or deburred. The nozzles produce a multi-zone spray pattern with a continuous effective cleaning zone. A water recycling and pressurizing system collects the used water, separates out the oil and grease contaminants to a level of about 5 ppm, and pressurizes the pure water to about 3,000 psi for washing operations or about 6,000 psi for deburring operations.

Claims

1. A robotic wash cell for washing a contaminant such as oil or grease from a surface of an object, said wash cell having a supporting surface and a source of high-pressure fluid, the object being placed relative to specific predetermined coordinates inside said robotic wash cell, said robotic wash cell comprising:

a six-axis robotic arm having a fixed end rigidly secured to the supporting surface, a proximal end, and component members joined to form six joints and six axes of rotation, said fixed end defining a main axis of said robotic arm, and the surface of the object being offset from said main axis;

an end effector having a nozzle, said end effector being secured toward said proximal end of said robotic arm, said end effector and nozzle having a direction of aim, the source of high-pressure fluid being flowably connected to said nozzle to controllably deliver the high-pressure fluid to said nozzle, said nozzle for a dispersing spray in said direction of aim, said dispersing spray having an increasing width dimension and an effective working range of up to about one foot; and

,

a control unit having a controller and an input device to selectively control said rotation of said joints to move said end effector and nozzle along a path of travel a desired distance from the surface of the object, said desired distance being within said effective working range of said spray, and said robotic arm articulating said end effector and nozzle and their said direction of aim to remain substantially normal to the surface of the object as said robotic arm moves said end effector along said path of travel, said spray substantially completely removing the contaminant from the surface of the object.

2. The robotic wash cell of claim 1, and wherein said fluid is pure water.

3. The robotic wash cell of claim 1, and wherein said width of said spray is substantially normal to said path of travel.

4. The robotic wash cell of claim 3, and wherein said object has a variety of surfaces and said six-axis robotic arm moves said end effector and nozzle along a series of particular paths in a multi-directional manner along each of said variety of surfaces, each of said particular paths maintaining said nozzle a desired distance within said effective working range of said spray from the surface of the object, and said robotic arm articulating said end effector and nozzle and their said direction of aim to remain substantially normal to the surface of the object as said robotic arm moves said end effector along each of said particular paths of travel.

5. The robotic wash cell of claim 4, and wherein said component members of said robotic arm include a base, first and second arm members, a wrist, and a mount with said proximal end, said base being rotatably connected to said supporting surface about a central axis of said base, said first arm member being pivotally connecting said to said base, said second arm member being pivotally connected to said first arm member, said second arm member having a first portion that is rotatably connected to a second portion along a central axis of said second arm member, said wrist being pivotally connected to said arm member, and said mount being rotatably connected to said wrist about a centerline of said mount.

6. The robotic wash cell of claim 5, and wherein at least one of said paths of travel is arcuate.

7. The robotic wash cell of claim 1, and wherein said end effector has an adjacent nozzle aligned parallel to said direction of aim and producing an adjacent spray, said sprays overlapping in said effective working range, and said sprays being slightly rotated to avoid intersection of said adjacent sprays.

8. The robotic wash cell of claim 7, and wherein said effective working range has an effective cleaning zone with a depth of about two inches.

9. The robotic wash cell of claim 8, and wherein said effective cleaning zone extends from about eight inches to about ten inches from said nozzle.

10. A robotic wash cell using recycled pure water for cleaning a contaminant such as oil or grease from a surface of an object, said robotic wash cell using recycled pure water comprising:

a recycling and pressurization system having a water supply of solvent-free water, an oil separator to separate oil from said water supply to a purity level of 5 ppm of oil or less, a filter to filter solids from said water supply to a purity level of 30 microns, and a pump to pressurize a portion of said water supply to a pressure of about 1,000 to 5,000 psi;

a six-axis robotic arm having an end effector with a nozzle in fluid communication with said pressurized portion of said water supply, said end effector and nozzle having a direction of aim to spray said pressurized water in a spray in said direction of aim, said six-axis robotic arm to move said end effector and nozzle a predetermined distance from the surface of the object and articulate said end effector to direct said direction of aim of said spray substantially normal to the surface, and said six-axis robotic arm to move said end effector along a path of travel while maintaining said nozzle said predetermined distance from the surface of the object and articulating said end effector to maintain said direction of aim of said spray substantially normal to the surface of the object as the end effector moves along said path of travel, said spray being returned via said recycling and pressurization system to said water supply.