Micropump including ball check valve utilizing ceramic technology and method of fabrication

#The present invention pertains to micropumps, and more particularly to a micropump including a ball check valve formed utilizing multi-layer ceramic technology for improved size and performance benefits.

#Laminated ceramic components containing miniature channels and other features, also referred to as microsystems, which utilize low pressure lamination ceramic technology, are currently being developed for use in microfluidic management systems. Of interest is the development of microsystems based on this multilayer ceramic platform in which highly integrated functionality is key. Monolithic structures formed of these laminated ceramic components provide for three-dimensional structures that are inert and stable to chemical reactions and capable of tolerating high temperatures. In addition these structures provide for miniaturization of component parts, with a high degree of electronic circuitry or components embedded or integrated into such a ceramic structure for system control and functionality. Potential applications for these integrated devices include fluidic management in micro-channel devices for life sciences and portable fuels cell applications. One application in particular is the use of ceramic materials to form microchannels and cavities within a ceramic structure thereby defining a micropump and miniaturized valves. Currently, micropumps are provided for use but require positioning on an exterior of a ceramic package, thereby utilizing valuable circuitry real estate.

#Mechanical pumps including ball check valves have been developed for use in conjunction with many devices. Many of these mechanical pump devices are cumbersome and complex consisting of several discrete components connected together with plumbing and hardware to produce the pump device. Accordingly, these types of mechanical pumps including ball check valves have not been found suitable for portable ceramic technology applications, or in other applications requiring minimal size and weight. In an attempt to miniaturize and integrate components for use in current microsystem technologies, there exists a need for a micropump including a ball check valve that provides for integration with a ceramic laminate structure. By integrating the micropump, or a portion of the micropump into the ceramic laminate materials, the surface area of the ceramic device can be utilized for other components, such as electrical interconnects or the like. To date, no micropump including a ball check valve has been developed utilizing ceramic monolithic structures in which the miniaturization and integration of the pump has been achieved.

#The novel features believed characteristic of the invention are set forth in the claims. The invention itself, however, as well as other features and advantages thereof will be best understood by reference to detailed descriptions which follow, when read in conjunction with the accompanying drawings, wherein:

#FIG. 1 is a simplified sectional view of a micropump with ball check valve according to the present invention;

#FIG. 2 is a simplified sectional view of an alternative embodiment of a micropump with ball check valve according to the present invention; and

#The present invention can be best understood with reference to FIGS. 1-3. In FIGS. 1-3 a micropump including a first ball check valve and a second ball check valve is provided. In the illustrated embodiments, the device is comprised from a plurality of stacked layers of green ceramic tape, which upon firing, sinter into a dense block of ceramic material called a fired package. FIGS. 1-3 will all show fired packages in which the individual layers of green tape ceramic will not be shown.

#Turning now to the drawings, and in particular FIG. 1, illustrated in simplified sectional view is a micropump including a plurality of ball check valves, referenced 10, according to the present invention. Micropump 10 is comprised of a plurality of ceramic layers 12, that once fired, sinter into a single device or package 13, as illustrated in FIG. 1. Device 10 has integrated and defined therein a first ball check valve 14 and a second ball check valve 30. First ball check valve 14 includes a fluid inlet channel 16. Fluid inlet channel 16 provides for the intake of fluid into device 10. A first microchannel 18 is provided in microfluidic communication with fluid inlet channel 16. It should be understood that anticipated by this disclosure is the combination of fluid inlet channel 16 and first microchannel 18, thereby providing for fewer component structures, or defined channels, within device 10.

#First microchannel 18 provides for fluidic communication between fluid inlet channel 16 and an inlet fluid cavity 20. There is provided in fluidic communication with inlet fluid cavity 20, a plurality of second microchannels 22 (discussed presently) that provide for the outake of fluid from inlet fluid cavity 20 during operation of micropump 10. Second microchannels 22 are in communication with a third microchannel 24 through which the pumped fluid flows from first ball check valve 14, to second ball check valve 30. Second ball check valve 30 includes an outlet fluid cavity 32. A plurality of third microchannels 34 provide for the movement of the pumped fluid from outlet fluid cavity 32 to a fourth microchannel 36, and subsequently into a fluid outlet channel 38. Again, it should be understood that anticipated by this disclosure is the combination of fourth microchannel 36 and fluid outlet channel 38, thereby providing for fewer component structures within device 10. In this particular embodiment second microchannels 22 of first ball check valve 14 and third microchannels 34 of second ball check valve 30 are formed to prevent the blockage of microchannels 22 and 34 by a ball (described presently) encompassed therein cavities 20 and 32 as illustrated.