Ink jet printer
AssigneesEpson Corporation, Kabushiki Kaisha Suwa Seikosha
InventorMitsuaki Maruyama
Life of this patent
Estimating the term…
Abstract
An ink jet printer includes pumped-forced circulation of ink through the printer head and a nozzle cap which together eliminate gas from the ink supply and overcome ink stagnation which adversely affect printing quality. Ink from a tank circulates through the printer head and returns to the tank while the nozzles are capped. A brief flow of ink from the nozzles completes a purging of the head prior to printing.
Claims18
An ink jet printer comprising:
- a printer head including a substrate, a vibration plate, at least one pressure chamber and nozzle formed by providing a gap between said substrate and said vibration plate, each said pressure chamber being connected to one of said ink nozzles;
- ink tank means for containing ink for printing;
- a reservoir having an inlet and an outlet each said pressure chamber being connected by a channel to said reservoir for receiving ink from said reservoir, said ink reservoir having a low hydraulic resistance to fluid flow from said inlet to said outlet relative to the hydraulic flow resistance through said pressure chambers, channels and nozzles;
- first tube means for connecting said ink tank means to said printer head inlet;
- second tube means for connecting said printer head outlet to said ink tank means, ink flowing from said ink tank means passing through said ink reservoir from said inlet to said outlet to expel gas bubbles and return to said ink tank means without loss of ink.
A method for expelling gas bubbles from a printer head, said head including an inlet port, an outlet port, an ink reservoir and at least one discharge nozzle for ink flow, said inlet and outlet port being connected to said reservoir, said nozzle being connected to a pressure chamber, said pressure chamber being connected to said reservoir, comprising the steps of:
- (a) blocking said at least one discharge nozzle by cap means;
- (b) forcing ink under pressure through said head from said inlet port to said outlet port;
- (c) releasing said blocking provided by said cap means until ink flows from said at least one nozzle.
An ink jet printer comprising:
- a printer head including at least one pressure chamber, at least one nozzle communicating with said pressure chamber;
- ink supply means for providing ink in said at least one pressure chamber;
- cap means for capping and cleaning said nozzle, said cap means including a flat portion and a curved portion and being mounted for rotation between an open position and a closed position, said flat portion being spaced from the discharge opening of said nozzle when said cap means is in said open position, said curved portion pressing against said discharge opening of said nozzle and stopping said nozzle when said cap means is in said closed position, said curved portion wiping said discharge opening when rotating between at least one of said open and closed position and said closed and open position, whereby said nozzle may be sealed when printing is stopped, exposed to permit printing, and cleaned in the sealing and exposing process.
Dependencies are inferred from the claim text.