Liquid cartridge and liquid pump

The entire disclosure of Japanese Patent Application No.2007-274729. filed Oct. 23. 2007 is expressly incorporated by reference herein.

1. Technical Field

The present invention relates to liquid cartridges for storing liquid and liquid pumps.

2. Related Art

A variety of liquid cartridges are available as containers for storing liquid. Among those containers, for example, small sized containers include ink cartridges for fountain pens and ink cartridges equipped in ink jet printers. Liquid cartridges can store liquid without leakage of the liquid. Because of this, liquid cartridges are normally structured so as to be readily handled for transportation and supply of liquid.

Liquid cartridges store a variety of liquid including not only simple liquid but also various kinds of dispersions. Representative liquid among them may be inks. When such liquid is stored for a long period of time, its compositions may settle and be separated. To address such problems, various methods are considered, including methods for mixing various kinds of dispersants in liquid. As methods for re-dispersing compositions in liquid, methods for shaking liquid cartridges and methods for stirring liquid in liquid cartridges are used. Among these methods, methods for stirring liquid inside liquid cartridges are very promising as the required space can be made smaller, compared to methods of shaking liquid cartridges. Moreover, when liquid is to be fed out from cartridges, the amount of the liquid may need to be adjusted appropriately, and the liquid may need to be pumped for transferring the liquid a long distance.

On the other hand, there are various devices for flowing liquid, such as, screw propellers for ships and various pumps. Also, fish fins may be considered as devices for flowing liquid. Such device mechanisms use particular shapes and movements specifically selected to effectively flow liquid. The structure and principle of fish fins may be applied to pumps. For example, Japanese Laid-open Patent Application JP-A-5-272497 describes a pump for flowing liquid by reciprocally rotationally driving a fin about a rotary shaft within a specified angle range. The document describes that the pump can be formed with smaller and fewer components. It is conceivable to combine the pump mechanism described in the document with a container for flowing liquid within the container.

However, for flowing liquid within a liquid cartridge or feeding out liquid from within a liquid cartridge, a mere combination of the aforementioned pump would not be suitable for size-reduction, as it requires large-scale mechanism and operations. Furthermore, in the case of a pump driven by a mechanism with a rotary shaft, bearings for supporting the rotary shaft, sealing for sealing liquid and the like are required. Such sealing also becomes an obstruction to size-reduction. Also, for example, the screw propeller mechanism has a drawback in that its efficiency considerably deteriorates when its rotation speed is increased in order to increase the fluid flow rate.

In accordance with an advantage of some aspects of the invention, it is possible to provide a liquid cartridge equipped with a novel mechanism for flowing liquid, and capable of stirring or flowing liquid therein.

In accordance with another advantage of some aspects of the invention, it is possible to provide a small-size liquid pump capable of flowing liquid within a pipe.

In accordance with an embodiment of the invention, a liquid cartridge includes: a container section for storing liquid; a plate-like vibration body submerged in the liquid for flowing the liquid; and a driver section for driving the vibration body in a thickness direction, wherein at least a portion of an end section of the vibration body in an in-plane direction continuously becomes thinner toward an end of the vibration body.

The liquid cartridge described above is capable of stirring or flowing liquid therein.

The liquid cartridge in accordance with an aspect of the invention may further include a flow path section that communicates with the container section, and the flow path section allows the liquid to flow therein.

In the liquid cartridge in accordance with an aspect of the invention, the driving section may vibrate the vibration body by flexing the vibration body.

In the liquid cartridge in accordance with an aspect of the invention, the driving section may vibrate the vibration body by shifting the position of the vibration body in its entirety.

In the liquid cartridge in accordance with an aspect of the invention, at least the thinner portion of the vibration body may be submerged in the liquid, and the liquid may be flowed with a speed component in a direction perpendicular to a thickness direction of the vibration body and in a direction in which the vibration body becomes thinner.

In the liquid cartridge in accordance with an aspect of the invention, the driving section may have a piezoelectric element.

In the liquid cartridge in accordance with an aspect of the invention, the vibration body vibrates with a frequency that may be a resonance frequency of the vibration body, or a resonance frequency of an entire body including the vibration body and the driving section.

In accordance with an embodiment of the invention, a liquid pump includes: a tube section for passing liquid; a plate-like vibration body that is submerged in the liquid for flowing the liquid; and a driver section for driving the vibration body in a thickness direction, wherein at least a portion of an end section of the vibration body in an in-plane direction continuously becomes thinner toward an end of the vibration body.

The liquid pump described above can be reduced in size, and is capable of flowing liquid in a pipe.