Apparatus for electrostatically isolating conductive coating materials

Apparatus for transferring electrically conductive coating material from a source to an electrostatic coating dispenser, comprising:

• a first pump and a second pump each having a reservoir which receives coating material, and means for discharging the coating material from said reservoir while substantially isolating the coating material from contact with air, said second pump being adapted to communicate with the electrostatic coating dispenser;
• a filling station;
• a first shuttle movable relative to said filling station between a transfer position connected to said filling station and a neutral position spaced from said filling station, one of said filling station and said shuttle being adapted to communicate with the source of coating material and the other of said filling station and said first shuttle being connected to said reservoir of said first pump to fill said reservoir with coating material;
• a discharge station;
• a second shuttle movable relative to said discharge station between a transfer position connected to said discharge station and a neutral position spaced from said discharge station, one of said discharge station and said second shuttle being connected to said reservoir of said first pump to transfer coating material therefrom, and the other of said discharge station and said second shuttle being connected to said reservoir of said second pump to transfer coating material thereto;
• means for moving said second shuttle to said neutral position while said first shuttle is located at said transfer position, and means for moving said first shuttle to said neutral position while said second shuttle is located at said transfer position.

Apparatus for transmitting electrically conductive coating material from a source to an electrostatic coating dispenser, comprising:

• holding means for receiving and discharging coating material;
• first transfer means for transferring coating material from the source into said holding means, said first transfer means including coupling means for transmitting coating material including a first coupling member, a second coupling member movable into engagement and disengagement with said first coupling member and means for creating a suction at one of said first and second coupling members in the course of disengagement thereof;
• second transfer means for transferring coating material from said holding means to the electrostatic coating dispenser, said second transfer means including coupling means for transmitting coating material including a first coupling member, a second coupling member movable into engagement and disengagement with said first coupling member and means for creating a suction at one of said first and second coupling members in the course of disengagement thereof;
• means for disengaging said first and second coupling elements of said second transfer means so that said second transfer means is electrically isolated from the electrostatic coating dispenser while said first transfer means transfers coating material into said holding means;
• and
• means for disengaging said first and second coupling elements of said first transfer means so that said first transfer means is electrically isolated from the source while said second transfer means transfers coating material from said holding means to said electrostatic coating dispenser.

A method of transmitting electrically conductive coating material from a source to an electrostatic coating dispenser, comprising:

• transmitting coating material from a source to one of a filling station and a first transfer device which are coupled to one another;
• transmitting the coating material from the other of said filling station and said first transfer device to the reservoir of a pump;
• transmitting the coating material from said reservoir of said pump to one of a discharge station and a second transfer device which are coupled to one another;
• transmitting the coating material from the other of said discharge station and said second transfer device to the electrostatic spray gun;
• uncoupling said discharge station and said second transfer device while transmitting coating material to said reservoir of said pump, and creating a suction within at least one of said discharge station and said second transfer device in the course of uncoupling thereof to prevent drippage of coating material;
• uncoupling said filling station and said first transfer device while transmitting coating material from said reservoir of said pump, and creating a suction within at least one of said filling station and said first transfer device in the course of uncoupling thereof to prevent drippage of coating material.