US 6,783,215 B2Granted

Ink container, inkjet printing apparatus, and ink supplying method

AssigneeCanon Kabushiki Kaisha

InventorsMasahito Yoshida, Naoji Otsuka, Hiroyuki Inoue, Takashi Nojima, Hitoshi Sugimoto, Shusuke Inamura, Yasufumi Tanaami, Takeshi Iwasaki, Noriko Sato, Yasuyuki Hirai, Takeshi Yazawa

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Abstract

In a supply system which includes an ink container for reserving a predetermined amount of ink to be supplied to a printing head and which is configured such that ink is intermittently supplied to the container from an ink tank, there is provided a structure that fundamentally eliminates waste of ink associated with an operation of charging the container to apply a required negative pressure to the head. An ink containing body in which a negative pressure can be generated because of its elasticity is provided in the container. After the ink containing body is expanded to introduce ink into the same by depressurizing the interior of the container, the interior of the container is pressurized to contract the ink containing body, thereby returning a predetermined amount of ink to the tank. A negative pressure is thus generated in equilibrium with an ink meniscus holding ability of the head.

Claims16

Dependent claims

An ink container that can be disposed halfway of an ink supply path connecting a printing head for performing printing by ejecting ink and an ink tank serving as a supply source of ink to be supplied to said printing head, comprising:

an ink containing body capable of containing ink introduced thereto from said ink tank in a state in which it is in fluid communication with said ink tank, said ink containing body supplying the ink contained therein to said printing head during printing and having a part that can be displaced in the direction of increasing an internal volume thereof to introduce the ink;
a housing having an inner space in which a pressure can be adjusted, said housing allowing said ink containing body to be contained in the space and allowing an increase in the internal volume thereof in accordance with the pressure adjustment;
and
urging means provided at said ink containing body for urging said ink containing body in the direction of increasing of the internal volume of the same to generate a negative pressure that is in equilibrium with an ability to hold meniscus formed at an ink ejecting portion of said printing head,
wherein said ink containing body has a flexible structure which expands when the inner space of said housing is depressurized to increase said internal volume and which contracts when the inner space of said housing is pressurized to decrease said internal volume;
and said urging means generates said negative pressure when the inner space of said housing is pressurized to decrease the internal volume of said ink containing body after the internal volume of said ink containing body is maximized as a result of depressurization of the inner space of said housing.

3 more elements

A printing head unit comprising:

a printing head for performing printing by ejecting ink;
and
an ink container that can be disposed halfway of an ink supply path connecting said printing head and an ink tank serving as a supply source of ink to be supplied to said printing head, having:
an ink containing body capable of containing ink introduced thereto from said ink tank in a state in which said ink containing body is in fluid communication with said ink tank, said ink containing body supplying the ink contained therein to said printing head during printing and having a part that can be displaced in the direction of increasing an internal volume thereof to introduce the ink;
a housing having an inner space in which a pressure can be adjusted, said housing allowing said ink containing body to be contained in the space and allowing an increase in the internal volume thereof in accordance with the pressure adjustment;
and
urging means provided at said ink containing body for urging said ink containing body in the direction of increasing of the internal volume of the same to generate a negative pressure that is in equilibrium with an ability to hold meniscus formed at an ink ejecting portion of said printing head,
wherein said ink containing body has a flexible structure which expands when the inner space of said housing is depressurized to increase said internal volume and which contracts when the inner space of said housing is pressurized to decrease said internal volume;
and said urging means generates said negative pressure when the inner space of said housing is pressurized to decrease the internal volume of said ink containing body after the internal volume of said ink containing body is maximized as a result of depressurization of the inner space of said housing.

6 more elements

Dependencies are inferred from the claim text.